So I've got a 21, 40, and 50 and am looking for a portrait/tele lens. I stopped by my local camera shop and saw some (very beat up) Elmar 90mm Collapsibles-I like the fairly compact nature of the lenses (and my 50's an Elmar, so they'd match), but am not if that's what I should go for. I'm thinking around 90mm is what I want-I have an 85/90 with all my other systems and like the length as a good all-around tele. I am looking for compact, light, and fairly inexpensive. Second to all those comes speed-wider apertures would be nice, but I think I'd be fine with f4-my 40's a 1.4 and 50's 2.8, so I've got speed there if I need it and I'd prefer my first tele to be compact over fast. I would have picked up one of the Elmars from my local shop to at least test out, but they were beat up-tons of cleaning marks and scratches on the front element and still asking $325. Thoughts?