Among that lineup, the only lens I currently have is the Sigma 17-70 and I know you're really going to like it.
It's my main walkaround lens.
In my main lineup, I'm looking to replace the 100-300, with the 55-300, most likely. It's expensive, but the front rotating element on both the Sigma APO and the Tammy 70-300s would probably drive me up the wall if I wanted to use a polarizer with either one of them.
If I had the extra money to blow, I'd seriously consider getting a combination of the 50-135 and the Sigma 135-400. There's a part of me that would like to complete my FA limited set, but the more sensible part of me says to spend the money that I would spend on the 77 Ltd on the 50-135, keep the 100-300 until I can afford the 135-400 and never mind the primes.
Heather