The SARs are made at the same factory/arsenal (Cugir) as the Romanian military AKs for their own use, so they're pretty solid. I've read here and elsewhere that WASRs are made at the Sadu arsenal that is more or less reserved for export weapon purposes and is thought less of quality wise. I could have sworn some earlier WASRs were made at the Cugir arsenal too but maybe that is wrong.
I've got an SAR1 that I will probably never get rid of, it's a solid great shooter IMO. I wish I had not gotten rid of my SAR2 as well. But then again the few WASRs I've run into at the range and such were pretty darn good it seemed too (all standard 7.62x39 WASRs, haven't seen any WASR2s or 3s or whatever they're calling them), so...
It seems those shopping for WASRs have the same things to look out for that the SARs did, check for badly canted sights or gasblocks, etc. I've actually seen nicer looking wood on the WASRs of late, my SAR1 and 2 had the ugliest, thickest varnished crap on the stocks I've ever seen. Stripped and cleaned up nice for a DIY project though... I have also read of WASRs being inaccurate compared to other AKs, but I'm not sure I buy that. Kinda up to the individual whether it's worth $50 more or not...