I own an SU-16B and I've put several hundred rounds through it. It's been accurate and reliable; I like it a lot. The one thing I don't like is that the picatinny rail on it appears to be crooked, it's just about impossible to zero a red-dot sight. I have been able to zero the iron sights, but I had to file down the front sight after adjusting it all the way down to get a good zero.