Apeks AT20 or SB S550

[MrSam]

Ok I got it thanks. If you want to self service I'd go with the Apeks set. If you want best resale I'd go with SP. The MK25 is reported to be one of the best piston 1st stages, certainly SPs flagship 1st stage. The SP will likely breathe better. If you go with the SP I'd try for a SP octo.

Thanks, that was the plan all along (well aside form the octo, I honestly have too many second stages at the moment, some need to be sold!).

Do 1st stages really make a noticeable difference? I know a balanced diaphragm is best for cold water, but does it really matter if you use a balanced diaphragm or piston in regular-temp water? Is there a noticeable difference in performance?

 

[buddhasummer]

I'm sure someone with more knowledge will chime in but it is my understanding that piston regulators generally have higher flow rates, the MK25 I believe has the highest flow rate. The flow rate only matters to a point as up to a certain level the 2nd stage then becomes the limiting factor. Having dived Apeks diaphragm regs and Atomic piston regs I could not tell any difference.

 

[MrSam]

I'm sure someone with more knowledge will chime in but it is my understanding that piston regulators generally have higher flow rates, the MK25 I believe has the highest flow rate. The flow rate only matters to a point as up to a certain level the 2nd stage then becomes the limiting factor. Having dived Apeks diaphragm regs and Atomic piston regs I could not tell any difference.

That's what I was told by the owner of my LDS as well. "Unless you're sitting there assessing EVERY breath you take, you really won't notice a difference. Spend the extra cash on a balanced 1st and 2nd stage, and don't worry about the rest."

 

[ams511]

That's what I was told by the owner of my LDS as well. "Unless you're sitting there assessing EVERY breath you take, you really won't notice a difference. Spend the extra cash on a balanced 1st and 2nd stage, and don't worry about the rest."

Usually, differences in second stages are felt more than differences in first stages. Conceivably, you could tell the difference if working the first stage hard. Two divers on air, at depth, breathing hard, etc. In normal diving you are not going to notice much of a difference especially between an Apeks and a Scubapro MK25