I started T-Tapp about a year and a half ago. Sometimes I do it exclusively for a few weeks, sometimes I just mix it in with other workouts. But I've rarely gone more than a week without doing at least a short T-Tapp workout, because it really makes a difference in how I feel. I especially credit it with fixing my bad right shoulder, which had pained me for years. My posture is also much improved.
I started out with just "Instructional 1/ Basic Workout +", and took about a month to get comfortable with that routine, then bought "Instructional 2/ Total Workout". Although I've accumulated quite a few more T-Tapps, those two are the ones I reach for most, and all I really need. Last year (when I was tracking my workouts in a spreadsheet) I did "Basic Workout +" 51 times and "Total Workout" 31 times, making them by far my most used dvds. There's
a pretty good special going on for May, with those two workouts plus a few more. The Tempo workout in that deal is very good, and adds a little variety. I don't have the Barefoot one, but it sounds like something I'd like to try. Also, I think I saw a set listed on the Yaya Swap for like $35 recently -- you could check to see if that's still available, as well.
I agree that there's some good information in the forums, but to be honest, the atmosphere there kind of gives me the willies. I guess it's kind of like any instructor devoted forum; you'd feel awkward to bring up other workouts, plus there seems to be a big faction of homeschooling moms with a dozen kids, so I feel kind of out of place there. I guess I'm just saying this to let you know that if the forums don't grab you, that doesn't necessarily mean that you won't like the workouts themselves. They have a very different vibe (to me, anyway).