I have been tempted to get the CalDigit Thunderboltstation before but realised I do not tend to plug my rMBP into my monitors on my desk much at all (I have a hackintosh desktop there).
That being said, if it were my only computer I'd definitely see the value in it. I use a laptop at work and plugging into an Apple Thunderbolt display giving video, ethernet, keyboard, firewire external drive etc in one is very handy.