While I haven't built up TB14's, I certainly would love to do so soon. In Canada, it's always been more cost effective to just go with Mavic rims. My favourite wheelset is my fixed gear set that are Mavic Open Sports laced to Gran Compe Small Flange hubs.

Now, if I had to choose between Mavic Open Pro's and TB14's (given that they're in a similar price range), I'd go TB14's for the width bonus and aesthetic.

It also comes down to price: Mavic Open Sports (now Elite's) are great value and lace up nicely, but if you're willing to shell out a bit more, treat yourself to the TB14's!