wasr 10/63 ak-47

AIM has them: http://www.aimsurplus.com/acatalog/NEW_AK_WASR_RIFLE_w__Bayonet_Lug___Muzzle_Break.html Is there any difference other than the bayonet lug and threaded barrel? Are the receivers qualitatively better? I take it these will have the usual grinded out magwells? Any info anyone has...