I heard they both make great OH's and instrument mics. What I wanted to know was what were the distinct differences. DJL Pointed out the the KSM27's picked up alot more of the room, maybe they'd be great in an iso booth. On the other hand, studio citizen points out how bright the MXL 603's are. this makes me wonder if they were very good for accoustic guitar. The guy at muzac stop suggested I get the MXL's for OH's and said he can get me a matched pair for $400 CDN with carrying case and shockmounts. Again, that's affordable by CDN standards. I never got a CDN quote on the KSM27's.
Anything else I should consider? Right now I'm gonna go check out the specs, but I'd rather hear about the real life experiences. Thanks Alot guys.