One of the things that had always bugged me with the 552 is the issues i read about some people were having with it (IIRC the rod holding the recoil spring breaking, effectively killing the gun), which is why they made the 553. Lately I've convinced myself that i NEEDED the 553 conversion but then thought that for the price of the conversion kit, I'd much rather have a factory 553 - which will be my next project - a NR flattop CQB with factory 553 operating system
I know I'm a bit retarded in how I let stupid little things bother me like that. I mean after all these guns are supposed to be for shooting paper only right? so who cares if they are not 100% reliable. I remember when I got my NR HK USC and after doing the folding stock conversion thinking that it was the perfect rifle. Then i got thinking that it kinda bothered me that most of the rifle was plastic and felt a bit flimsy so I started looking around for rifles of similar size but made of metal which is how I decided to get the CQB in the first place.