I have the Tascam US-122 and I've used it for a couple of years now. It's a USB box that provides both audio and MIDI interfaces for me - and I like it.

Currently I use Sonar for my recording - but eventually I will probably make the jump to ProTools eventually. The folks over at DigiDesign have competitive upgrade packages that are nice... I can turn in my Sonar software and my Tascam hardware for a price break on the ProTools software and one of their new hardware interfaces...

When and if I am ready for that step, I'll do it - but until then, this Tascam box does quite well for me.