I won one in a raffle last month. Due to being on tasking, I haven't really had any time to perfect my review. I will say, that the real steel and airsoft parts I have tried on this GBBR all fit perfectly. Overall, the only thing that I can see as being any kind of bad part is the bolt itself is plastic. Had they actually made it metal like the bolt carrier, I would have a lot less worry with the rifle itself.
As soon as I can, I will finish up the review, and post it and the pictures on here for everyone.