just received my 13" rMBP 2.9 I7 8/512 refurb..can't tell the difference between a new one..absolutely pristine shape and I'm digging it. I currently have a late 2009 iMac 27"..debating on whether to sell it or just use it as a target display..will definitely wait for the thunderbolt display refresh before making a decision..so I'm in Mac heaven.
I am thinking of going that way, have a 09 imac too. Wasn't sure of the 13 or 15.