RE: filip rg
They just didn't use very heavy glass for the fuselage. It tends to crack fairly easily from what I've seen. It's not like it would cost them more to make it a bit tougher...I think they were just going for very light weight.
It's a really good flying plane, and I think it's worth the price, but you have to keep the fragility in mind, especially if you don't have a nice grassy landing area. Adding some heavier glass reinforcement ot the inside of the forward fuse shouldn't add too much weight though.