Consistancy will really depend on the reg on the HPA tank, and the gun. At least wiht CO2, you have a constant, CO2 expands at the same rate always... (dependant on tempurature, but its still constant, unless you are walking in and out of hot and cold buildings or something)
But rememebr this, in cold weather, some guns wont work. Fit of barrel, how rough they are on paint, feed style.. some wont do it.
Take for example, my old Panther VTS. +/- 2FPS on liquid CO2, quiet, light and dead accurate. Come winter, wouldnt last 3 min without chopping a ball. Same for my hurricane, good pointable, nice quality, hates the cold.
One thing to thin about is that HPA tanks wont get the same shots per weight as CO2. and with a good regulator and an anti-siphon tube, most guns will run great on CO2 (Ive seen Bushmasters, O3's, Shockers, Impulses, Ions, Angels, Vikings, Cockers, Mags... etc run on it)
Is it a good idea to get one, if it works for your situation, sure. HPA has its perks, and one of them is winter use. On a blowback that requires 650+ psi to recock, great idea for when it gets cold, and later on, you want to shoot $20 worth of paint a game, then hey, no frozen gun then.
Oh, JT, noids can handle it ok, its the LPR that will usually freeze before the noid has trouble, ask Carter
