I've had almost the same experiences (it coming through hell and back from noobs to dust, sand, rain, etc.) with mine and yes their hicapa's use CO2, but I had so many issues I just run propane. I'd highly recommend a SERPA. Hands down my favorite and it comes in so many styles! Only problem is its a bit finicky with inserting it into the holster. Coming out is pretty clean and easy. NEVER had it fall out!
And just to let everyone know, these are THE best loner GBBs you will find. Anytime we run out of AEGs to loan at games, I load this up and every time people come back telling me how much they love it. :mrgreen:
KJW basically cloned the marui design to the letter and dropped in some nice high flow valves, great nozzle, reliable mags (nothing like their old leaky ones), full metal, and on mine, the tanio koba grips which go for a lot aftermarket.
Thanks to the Marui based hop up it shots just like a stock AEG in terms of distance and accuracy. Ammo capacity sucks unless you have three or more mags as they go FAST.
I love it so much I'm looking to get another Hicapa one for my brother and my teammates are all looking into buying them now that they have their primaries figured out.