I had one and sold it. The rifle shoots well, is easy to disassemble and built like tank. Field strip is popping 2 pins. The roller assembly goes in an out easily. I never disassembled the roller system but it never got dirty. It's not a gas gun so it runs clean. It will also run steel cased ammo. PTR recommends it over surplus ammo of unknown quality. Some models like mine had a picatinny rail built in the the receiver which is preferred if you want the option of mounting an optic.
The rifle is heavy, mine about 10.5 lbs. The fluted chamber is very reliable but ruins your brass. The safety is impossible to engage without taking your grip off the pistol grip. You would need giant hands to accomplish this feet.
It's high quality HK clone. If you like the HK 91, you will like the PTR.