H2Odyssey Extra Air Source

[Kharon]

I think it depends on which EAS you get. The EAS 2 is unbalanced piston while the EAS 3 is balanced diaphragm.

H2Odyssey | Diving Equipment | Air Systems

Check out the links to the RG2V and RG3V first stages.

Yep. The EAS2 has 2 versions one with a couple more ports than the basic one (1 HP and 2 LP more I think). The EAS3 is a diaphragm. Thanks for the correction.

 

[UnixMarine]

First, kudos to you. I am a big fan of redundant air supplies, even for recreational divers. In my opinion, which is worth what you paid for it, that extra 6 cuft is a hell of a lot better than nothing. That being said, the smallest I carry is a 30 now a days, although I used to carry a 19. The key is to understand the limitations, except the risk versus the other options and to practice with it so it becomes second nature. Something else to consider is what are you going to hand someone else who is OOA? You H2Oddysey or your octo? Does one get I. The way of the other? This is something you should practice, especially if you have a regular dive buddy.