I'm using a cheap nameless USB2 unit that has a floppy drive and 6 way card reader all built into a a standard 3.5" bay unit. It didn't need any drivers and 'just worked', other generic card readers have all 'just worked' too.
Sorry not to be more specific, but so far everything with Windows 7 has just worked without any problems (excepting an obscure bug with the Contour Shuttle Pro which disappears after switching users).
Paul