Upgrade set for sniper rifle CM.700/700A/708 - 575 FPS [CYMA]

My Cyma 700-U has already been upgraded with exactly this piston. I bought this replacement nevertheless, as a stock piece, also because of the seat (the tiny ball bearings have an annoying tendency to disappear, once the spring-loaded tension on the seat is lost). I know how well this piston works, so I did not need any confirmation about this from another reviewer. That means that I can recommend this piston for any VSR10-type cylinder from my own experience to anyone else who is looking for such a replacement. I did not test the spring that came with the package, but that's only because I already tweaked my Cyma 700-U to be at 2.3 Joule, with some other springs that I had to test, one after the other. So, I'm not in a hurry to also test this one right now. Anyway, you never can have enough replacement springs.