It's ok; although in this building it's very susespectible to interferance when naighbors use phone/etc... It DOES work through 4 levels of concrete on our roof though.. (last party we had a bbq on the roof; I was actually streaming music using my laptop from the roof!)

This card is better then the linksys; not sure about the SMC as I've never used theirs..

Personally, the best access point that i've had is the apple airport (it died on me though:( refuses to startup now..) - but I feel the range/reliability on that was much better...

-mark