I have exactly the setup but I made the wrong choice for my monitor.
I had a non-retina 15" MBP and bought the high end Dell UltraSharp U2713H monitor. It's 27" and highly regarded as a high-end monitor; comes with calibration software (lobotomized version of X-rite iDisplayPro) It also have gerzillion input options - from vga to DVI to HDMI to displayport and Minidisplay port. Since the Minidisplay port is the native port for the MBP it gave me the resolution I need without mucking around with adapters etc. (btw, minidisplay port on the Mac has the same physical form as the Thunderbolt port and the video signal is a subset - so yes hook up your Minidisplayport monitor to your Thunderbolt connector is ok.) I calibrated it with my iDisplayPro calibrator and all is happy...
...until I upgraded my computer to the new 15" Retina MBP. Well, guess what ... in addition to having no DVD drive (I don't miss it) it also has no ethernet connection. I'll have to use one of the 2 thunderbolt ports for an ethernet donggle. What a pain with all the stuff I have to hook up when I set my computer down on my desk - the ethernet, the connection to my external disks (TimeMachine and photo disks), the Monitor, the USB to my Wacom tablet, speakers etc. So, I shell out $300 and bought a Thunderbolt Hub (I have tried both the Matrox and the Belkin) so that everything can be left hooked up and all I have to do when I set my MBP down is connect one Thunderbolt cable. Voila.
So, why the wrong choice of monitor? If I had known, I would have purchased the Apple Cinema Display - it basically have the Thunderbolt hub built-in with RJ45 ethernet port, 3 USB's, audio, and extra thunderbolt port - so all you have to do is connect the Cinema display to the MBP via the thunderbolt port. So, for the price of the Dell UltraSharp and the Belkin Thunderbolt hub, I could have bought the Apple Cinema Display!
Also, trying to match the color of the Dell Ultrasharp with the MBP's LCD screen is a pain - even with the x-rite iDisplayPro gadget. I think the Apple Cinema Display would be a much easier match!
Hope this helps.
Yau-Man