Scuba_Noob
Contributor
I have an older Aqualung model on mine. The suggestion is to have the first and second stages of your pony bottle to be simple (but quality) so that there's fewer chances for anything to break down. It NEEDS to work in emergencies, so it's worth spending the extra for a good reg - it doesn't have to be expensive. A pony bottle in rec cases should be used in emergencies only (or when practicing using it for emergencies), not as an extension to your dive time - if you want to extend your dive time, get a bigger tank.
At less than 24 dives, adding a pony bottle might make you too task-loaded and mess with your buoyancy (while you're still learning how to maintain proper buoyancy). You should probably not dive alone, even with a pony bottle. It might give you bad habits, like sucking your primary tank very low or not paying attention to your gauges, just because you have a back-up.
My suggestion is to wait until you have a lot more experience (100+ dives) before you get a pony bottle.
At less than 24 dives, adding a pony bottle might make you too task-loaded and mess with your buoyancy (while you're still learning how to maintain proper buoyancy). You should probably not dive alone, even with a pony bottle. It might give you bad habits, like sucking your primary tank very low or not paying attention to your gauges, just because you have a back-up.
My suggestion is to wait until you have a lot more experience (100+ dives) before you get a pony bottle.