I have had a GSG for about a year now--early on it broke a barrel bushing (sheared the ears) and I replaced it with a stainless regular old 1911 bushing. the washer at the back of the guide rod also disintegrated--replaced with a plumbing (nylon faucet washer) which fit it perfectly and gives me a nice buffer. I have replaced the sights with a Warren/Sevigny set up--note the sight cuts on the slide are almost Novak cuts. I also ended up shaving down the grip safety to work more easily. This gun now runs amazingly well, and is quite accurate. It will shoot just about anything, but I feel more comfortable with Federal Match 40gr lead rn. The trigger is also about 4lbs and smooth. This gun is set up basically just like a 1911 except for the barrel which is pinned. Lots of interchangeable parts!
One of my kids that I coach has a Chiappa .22 and that gun has been problematic--doesn't feed anything well except mini-mags, and last Saturday broke the barrel bushing ears off. The trigger is somewhat gritty and heavy--reset is pretty long. I still have to contact the distributor for replacement parts. I spoke with them regarding a slide safety spring which commited sucide on my work bench somewhere. They were very nice and are going to ship a replacement spring right away. Hopefully I can get this gun going nicely--I'll report back.
Also Note: The GSG mags are very well made and go about $30 ea. Chiappa mags are all plastic and don't inspire confidence. Don't know their cost.