I have had one for about 6 years, the piston will go out at some point and replacing with full metal teeth will have it run forever I would also recomment a spring guide upgrade since (at least of the ones 6 years ago) they used a metal ring that just sits on the base of the guide to simulate a ball bearing spring guide and that ring can come loose and catch the spring or piston. I also burnt out a trigger but thats because I ran an 11.1 without a mosfet on it but all things considered mine shoots very well decent ROF and good reliability other than the 2 little things mentioned above.