What is the real difference betweeen S600 ,S620i and G260

[LanceRiley]

Im going long hose. i have an existing s600 and air2. so i'm gona ditch the air2 for a regular inflator. then I'll need another 2nd stage.

I could... keep the s600 as primary on a long hose. or as a backup in a 22in bungeed reg.

but what should i get? another s600? a s620ti? or a G260

1. ) s600 - would just be a mirror to what i have familiar and when it comes to overhaul easier for the guy doing it

2.) S620 ti - an upgrade to what I have an will be a primary while the old s600 as a bungeed backup

3.) G260 - this one i duno.. some say breathes easier. but i know is heavier weight.

 

[lexvil]

I don’t have a 620 ti but I do have a 600 titanium core (same thing pretty much) and I have 3 G260’s, when tuned you would be hard pressed to know the difference. The old metal barrel 600 is a little heavier than the Ti, the 260 is heavier and a little bigger, they all have the same internal capacity and all can move air better than you can use it. I would go with whatever you find the best deal on.

 

[LanceRiley]

thanks!

sometimes techy divers in the group push for the g260 i just find it BIG and heavier although not by that much.

thanks

 

[lexvil]

thanks!

sometimes techy divers in the group push for the g260 i just find it BIG and heavier although not by that much.

thanks

All 3 are great, I like the 260 because I find them at better prices and they do have a few extra features like being able to switch hose inlet side, if you ever needed that. The best deals on s600’s I’ve found are the earlier ones with the plastic barrel, I like the lightness of those 600’s over the chrome barrel ones.

 

[shurite7]

The inside (barrel / housing) of the S620Ti is slightly different than the S600. The S620Ti is made of titanium making it lighter and more resistant to corrosion (I forget the actual term for the green build up from salt water - hopefully someone knows and posts it) build up. The exhaust-T on the S620Ti was designed to make it easier to remove the gas (exhaling) from the second stage. Several people have told me they can feel a difference with the S620Ti.

The G260 is a continuation of the popular and successful G250, and was designed for tech divers. For example, the friction washer is part of the cover so that a diver can remove the cover without fear of loosing the plastic washer, whereas the friction washer is a separate component in the S600/S620Ti second stages. One can switch hose inlets, think side mount diving, as lexvil mentioned above. It is heavier than the S-series, but not noticeable underwater. It is quite rugged and holds up well in cold water. From a servicing point of view, the G260 is easier compared to the S-series.

When it comes to the inhalation effort, you'll be very hard pressed to notice a difference between the three (four if you count the A700) second stages.

 

[rhwestfall]

Verdigris

 

[Johnoly]

... (I forget the actual term for the green build up from salt water ...

?? Oxidation Bloom ?? Typically found on plated metals that have been compromised.

 

[LanceRiley]

The inside (barrel / housing) of the S620Ti is slightly different than the S600. The S620Ti is made of titanium making it lighter and more resistant to corrosion (I forget the actual term for the green build up from salt water - hopefully someone knows and posts it) build up. The exhaust-T on the S620Ti was designed to make it easier to remove the gas (exhaling) from the second stage. Several people have told me they can feel a difference with the S620Ti.

The G260 is a continuation of the popular and successful G250, and was designed for tech divers. For example, the friction washer is part of the cover so that a diver can remove the cover without fear of loosing the plastic washer, whereas the friction washer is a separate component in the S600/S620Ti second stages. One can switch hose inlets, think side mount diving, as lexvil mentioned above. It is heavier than the S-series, but not noticeable underwater. It is quite rugged and holds up well in cold water. From a servicing point of view, the G260 is easier compared to the S-series.

When it comes to the inhalation effort, you'll be very hard pressed to notice a difference between the three (four if you count the A700) second stages.

wow! this is detailed. thanks!

 

[rsingler]

If you're going tec, there are really two considerations to balance, and unfortunately, they're mutually exclusive when it comes to the S620Ti vs G260.

When it comes to problem solving underwater, the G260 is made for it. You can disassemble it and fish out whatever piece of junk made your exhaust valve stick open, so it doesn't breathe wet anymore. You could close the valve to the first stage and work the lever a bunch to dislodge a piece of grit. You could (theoretically) pluck out a piece of ice.
But having a problem like that and NOT thumbing the dive is open to debate. You already have a second (or third) regulator, so you could say you don't need to fix it.

Yes, you can remove the cover on the S620Ti (if you leave out the pin), but there is an extra part to lose during your repair. It's not designed to screw back in to exactly the correct amount of diaphragm compression like the G260. Instead, you need to align the pin hole.

Now for the other argument.
With new designs, also as noted above, you're hard pressed to feel a difference when you take a breath. Manufacturers have recognized this, which is why the new focus is on exhalation WOB. There are just not that many more improvements to be made on the inhalation side.
As noted above, the S620Ti (and the new D420) were specifically designed to decrease Work Of Breathing on the exhalation side.
As a tec diver, this is not insignificant. When moving deep air (not trimix) at several atmospheres, the total WOB can be significantly reduced by attention to the exhalation side of the flow loop. That helps prevent a CO2 hit, which can in some cases be fatal.
I think I can feel a difference in resistance to exhalation between those regs. But if you're only going to dive trimix below 100 feet, it's a moot point, because total gas density is so much less with helium.

The G260 is rugged, repairable, and can be configured for left side hoses.
The S620Ti has a lower work of breathing on the ANSTI machine, and maybe in your mouth with thick air.
Two very different choices.

 

[lexvil]

Just a note, all 3 of my G260’s have the lock pin for the front cover.