Bought my WASR 10/63 five+ years ago, cherry picked it from a bunch the vendor had at a gun show. No problems, no malfunctions to speak of. No trigger slap and it does have the Tapco G2 trigger. The bolt did catch on the hammer a little at first but only when I hand cycled slowly. Never a stoppage when firing and it did smooth out over time. (This is a common issue with the WASR.)
It was old enough to be a ban gun so had the welded muzzle nut which I hacksawed off and screwed on a flash hider. No bayonet lug either but the sights and gas tube were straight. It also didn't have the triangle marking that's supposed to indicate WASRs that passed military inspection - so mine might have military reject parts but it doesn't seem to matter. I've been very satisfied. It has the original chrome lined barrel, I'm not sure if today's WASR has that barrel or a non-chrome lined US barrel. Hear reports both ways on this.
The biggest issue with assembling an AR isn't so much getting the parts together right - it's getting the right parts together.
US Army 1966-69, VFW Life Member, Retired Geek