old scubapro vs new (G250 vs. G250HP)

[raposarose]

I have seen some threads where people lament about the good old days of the original Scubapro G250 second stage. They claim that it is so much better than the G250HP for a variety of reasons -- the new one is too complicated, it has inferior materials, etc.

I am curious, is there really that big of a difference? Are there any advantages to the new one? Are these folks right or do they really just like it because it is older. It seems like most messages here that talk about old vs. new scubapro products discount the new ones. But on the otherhand people still like Scubapro regs in general.

Some of the old regs mentioned aren't really that old either -- like from 1996. Does 7 years make that big of a diffence? What are your opinions on older vs. new scubapro regs in general and the G250/HP in particular?

Looking forward to your replies.

 

[redacted]

The 250HP is the same design as the S600. It has the seat saver feature which should make that LP seat last longer. It takes about a dozen o-rings while the G250 takes half that. Although each is a potential failure point, o-rings are very reliable as lonmg as they are installed correctly. And if you really want a seat saver feature on an old G250, just store it with the purge button depressed. Performance wise, you shouldn't be able to tell the difference in WOB. Some favor the older metal barrel over the newer composit barrel as it is perceived to reduce dry mouth. So factor in any cost advantage and flip a coin - you can't go very wrong.

This from someone who put the Mk20/G500 on the shelf to dive Mk5/Mk10/R109 (metal 2nds).

 

[DA Aquamaster]

The G250 HP has to be subdivided in to an A and B configuration.

The "A" configuration is basically the "old" G250 design utilizing the new and improved S wing poppet design and a modernized adjustment knob. It has a slightly different balance chamber than the G250 to accomodate the slightly longer poppet assembly.

The G250 HP "B" configuration also uses the S wing poppet but has the adjustable balance chamber used on the S600. When peopel talk G250 HP they normally are meaning G250 HP "B" configuration. The seat saver feature has been dropped on all of the SP regs and so the older G250 HP B's will have it and the newer ones won't.

The old Adjustable and Balanced Adjustable regs can be upgraded with the new poppet, balance chamber and spring to near G250 HP "A" status in that they lack only the VIVA adjustment but none the less breathe exceptionally well with a very durable smaller profile metal case to boot.

I don't think the G250 HP "B" configuration breathes all that differently from the G250 HP "A" and is in fact potentially an even better performer in that it is just an oversized S600. But the "B" configuration does require some additional tools to adjust the balance chamber properly and this may lead to less than 100% performance if it is not done correctly.

SP is ditching the seat saver feature and along with it is changing the balance chamber design to eliminate the need for a special adjustment tool to seal off the end of the balance chamber. The new design will allow an air on adjustment with only a screwdriver - much easier for the tech to adjust properly.

Incidentally, the G500 came in a US produced version which was exceptional (ID = all black purge cover) as well as a later european produced version that was not as good a performer (black and grey purge cover) due to being detuned a bit to meet european standards. But the good news for euro G500 owners is that like everything else scubapro, they can be upgraded, in this case to S600 status.

 

[raposarose]

Thank you for the detailed responses! I had no idea that there were two configurations of the G250HP.

All the best

 

[DA Aquamaster]

Thank you for the detailed responses! I had no idea that there were two configurations of the G250HP.

Scubapro is evolutionary in their design philosphy so they tend to build upon older models with improvements that are normally able to be retrofitted into older models. For example you can stick the newer G250 HP "B" configuration guts into an older G250 case.

The old metal "Adjustable" 109 second stage was improved with a balanced poppet assembly in the early 80's and all the Adjustables can be upgraded to "Balanced Adjustables". The "Balanced Adjustable" itself has had four major configurations to reflect improvements in poppet design including those used in the G250 and the current S wing poppet used in the G250 HP, G500, G550 and S600. The parts cost to convert an Adjustable to the latest Balanced Adjustable configuration is under $20.00, so it is a cheap way to get excellent performance out of a second sage that could be as much as 30 years old.

And if you are like Awap and still use one of the old 109 based metal stages no apologies are required. With the combination of their original metal orifices and the current S wing poppet they offer exceptional performance with out of the water cracking efforts in the .5 to .6 range and exhalation efforts of .4 to .5. In the water, they are stable with cracking efforts as low as .8 to 1.0. Very good perfromance by any standard. The metal case also offers excellent heat transfer in cold water situations and tends to prevent drymouth compared to the newer stages with plastic air barrels. The metal case also uses the same diaphragm as the G250/G250HP but does so in a smaller and lower profile case as less thickness and bulk is required with brass compared to composite materials to get adequate strenght.

All in all, I still prefer a fully upgraded Balanced Adjustable to a G250 or G250 HP.

 

[Genesis]

I hate the newer S600/G250HP "all plastic" models; they give me horrible cottonmouth that I just can't get around.

The G250, on the other hand, has the metal air barrel and it doesn't do the same thing to me. I can dive deep and long on that that not have problems.

I bet the metal-cased regs would be even better, but I don't have any of those.....

SP, IMHO, has taken the cheap rather than the good path here.

 

[raposarose]

The metal case also offers excellent heat transfer in cold water situations and tends to prevent drymouth compared to the newer stages with plastic air barrels. The metal case also uses the same diaphragm as the G250/G250HP but does so in a smaller and lower profile case as less thickness and bulk is required with brass compared to composite materials to get adequate strenght.

All in all, I still prefer a fully upgraded Balanced Adjustable to a G250 or G250 HP.

That is the main reason I asked the question. I am new to scuba as of this summer and got a good deal on a Mk18/G250HP set. Then I read a lot of posts about how much people preferred the older Scubapro G250s. I was trying to get to the bottom of what exactly the differences are. Well, I have what I have so probably it is not good to be overly concerned now. It is still good information.

 

[DA Aquamaster]

SP, IMHO, has taken the cheap rather than the good path here.

I agree with you there. I suspect it was much cheaper to mold a graphite resin case than to form one from brass, silver solder both the air barrel and mount for the exhaust T and then chrome plate the whole assembly. By current standards the older SP metal second stages were works of art. And as an extra benefit they were very durable. You can drop a tank on the older metal second stages, pound out the larger dents and go diving. You can't do that with a pastic second stage.

Similarly SP cited concerns with corrosion when it went to nylon orifices and there was some truth to that in poorly maintained regs. But I really suspect that motivating factore was unit cost of production. The nylon orifices are ok but are more fragile and I really prefer the older chrome plated brass orifices in terms of durability and adjustment potential.

 

[Genesis]

Similarly SP cited concerns with corrosion when it went to nylon orifices and there was some truth to that in poorly maintained regs. But I really suspect that motivating factore was unit cost of production. The nylon orifices are ok but are more fragile and I really prefer the older chrome plated brass orifices in terms of durability and adjustment potential.

The Nylon orifices bite.

The brass ones can be cleaned up in some vinegar for a few minutes, even if badly corroded, and are just fine.

Its the cheaping of products, and SP along with most of the others are WAY guilty of this - of course they don't cheapen the price!

 

[pescador775]

The 109 brass seconds were good regs by 70's stds. However, the 250HP is a much better breather and, most important, the mouthpiece is light. The 109 causes jaw fatigue. There was a tendency for the adjustment knob of the brass second to bind with salt corrosion and the unbalanced poppet needed frequent adjustment. However, with yearly maintenance, the 109 was extremely simple and reliable, very rugged. The 250HP is quite complex and plastics are always questionable in severe environments like diving. Give a little, get a little.