I listed it for 600, got a million replies, but sold to the first one, who turned out to be a sh*t of a hassle, but I wanted the money quick, and it left for 595. Could've went for so much more if I just listed it a bit higher...

The Concept is a 53cm, with a 53.5 TT and 53 ST
My IRO was a 50cm, with a 51.5 TT and 50cm TT
So there's actually quite a bit of difference, it's just not too noticeable because the Concept has oversized tubing.

Darn, I didn't realize swapping a crankset would cost $60 at the LBS. First thing tomorrow I'm going to the Bike Kitchen and doing it on my own. Doesn't hurt to learn how to do something like this either