You can get a Retina for that price and a much better machine at that. To move this you need to come down well below the entry price on the Retina.
If you build this exact machine today it's $2349. And it's the 2012 with upgraded processor and USB 3.0...
Unless the $2550 is the MBP + Thunderbolt display, then it's a good deal. Not clear though.
See my full mod list in my garage