Recommendations for a new primary second stage

[Biz2000]

I've been getting ready to acquire a pony bottle and begin thinking about setting up for doubles, however I'm indecisive on what my new primary second stage should be... I currently run a pre-2012 XTX50 as a primary second and an ATX40 as the octo, all on a DS4 first stage. Any opinions and elaboration would be appreciated, looking for cold-water, tech-oriented equipment.

 

[Biz2000]

I've been getting ready to acquire a pony bottle and begin thinking about setting up for doubles, however I'm indecisive on what my new primary second stage should be... I currently run a pre-2012 XTX50 as a primary second and an ATX40 as the octo, all on a DS4 first stage. Any opinions and elaboration would be appreciated, looking for cold-water, tech-oriented equipment.

 

[crofrog]

All your second stages should be the same with the exception of potentially not using a balanced second stage on your necklace. You’re going to spend as much or more time on your stages than your back gas in tech diving.

 

[DiveLikeAMuppet]

Your primary and backup regulators (first and second stages) on a twinset should be identical.

DS4 is nice for stages, with a twinset you get slightly better routing with DST.

ATX40 and XTX50 are both fine. Not sure how the pre-2012 looks like - I found the newer version a bit too large for stages but fine on a twinset.