the parts on the merlin look pretty okay to me.

i'd personally wait. if you could talk down either seller (maybe not the merlin since it's tall for you) into $300-$400 (bargain with ANYONE on CL even if it doesn't say OBO, never hurts to try) it'd be hard to pass up though, especially the r600 because i'm assuming it has at least DA 7700 without any damage on the bike.