I use my TiPX as a secondary / dual wield [with rifle].
Trained my left hand to use the pistol (i'm a righty). Now I'm just about equal in accuracy with my left hand, and clip changes and safety on/off actually feel more comfortable in my left hand.
I got a stock x-7 barrel, adds 2 inches to the stock barrel, and picked it up for $20.
I wanted a little extra length, but not a lot. Most of the barrels I looked at were stock length (hammerhead, etc) or a lot longer. And the barrels I looked at that were only 2 inches longer - that extra 2 inches was usually just a cosmetic add on like 'mock silencer' or other tips that didn't actually improve performance, just "looked cool" for the extra hindrance they offered [in bunker clearance, ease of holstering, etc].
Stock X-7 barrel took care of that, 2 inches extra of actual barrel. Plus I think it looks pretty bad-arse too!
I run with 4 mags.
I see drop off midway through 3rd mag... so I don't care about a few extra shots worth of gas efficiency, as I change my Co2 after 2 mags... I would rather waste a little Co2 and change 12g after 2 mags to make those next shots really count -> no drop off in any of my shots.
I was planning on First Strike mod, but I only unholster the thing when I'm in close quarters combat [like villages etc] and then my accuracy is just fine @ 50-70 feet. So I'm skipping the First strike mod to buy a few extra mags and call it a day. The fact that I don't have to pay $10 per mag in ammo is a big plus too...
I think I might look into the TechT MRT Bolt though...