I can only speak for the banshee because its the only quad I've ever owned. I bought mine used (2001) and the guy who owned it before me never once rebuilt. The pistons were worn and the reeds needed replacing. It was VERY simple to install my new wiseco pistons and Boyeson reeds. I've never had any mechanical expierience before hand and I stripped the bike to the frame and put it back together myself. After the rebuild, it feels like a whole new bike, and I've had NO problems yet except for my clutch cable melting on the pipe cuz I was a dumbass when I put that part on. Other than that dumb mistake, everything's been smooth for about 4 months now. If you can change gear oil, clean air filters, lube chains and tighten nuts and bolts every so often, theres no problem. The only drawback I really see is the low end. Its not really there. But I can still climb hills with the best of them. Uhhhh, Banshee don't really like to accelerate super quick when stock, but Banshees have about the biggest aftermarket following ever, so you'll always find upgrade parts.