I have worked with both the Vinculum-1 and Vinculum-2 parts. If you are seriously considering using one of them, I'd recommend the -2 as it appears the vinculum-1 is about at the end of its chain. The Vinculum-2 has a free IDE and downloadable code examples which mimic the behavior of all of the precompiled Vinculum-1 FW images anyway, and you have the ability to tweak things and add your own code to it. The documentation however, does leave something to be desired.
If I had a clean slate to start with, depending upon what I needed for functionality, I'd look strongly at the various ARM or other microcontrollers with USB controllers, possibly even consider ones that have available commercial USB stacks available for sale as well. Depends on what functionality you require and available development schedule time as to what makes the most sense.