I like to recommend SLR's to students who are starting out, besides the things mentioned already, a large and relatively bright (50mm f1.8 standard lens) viewing area is the norm, where as with range finders the larger and crisper windows and patches are usually only in the exceptional models.

I use both SLR and RF, but find that I am faster with a SLR and a good focusing screen. I really like my OM system as well, I just wish lenses were a bit less expensive. I have been keeping a look out for a nice 6x9 RF at a good price, as I have been liking my 6x6 RF, it will probably be my next purchase if I get lucky.