So I think that most of us using TDI over the past few years can say mostly good things about the product. Personally it's one of my favorite tools in the Tivoli Security stack being largely a non-developer type I feel empowered when I make cool things work with it. However most people would also agree that the products implementation of Swing might be a bit off. Just weird stuff like if you have a pop up window and you hit the enter key you expect the OK button to depress. And sometimes resizing windows is a little weird. I've even had to close the tool kit and reopen it sometimes just to make things work.
All that is pretty much gone with the new TDI 7.0. Oh and I believe there is a fix pack out already. I'm just starting to play with this new version. It takes some getting used to if your not comfortable with eclipse, but I look forward to working with it.
BTW, there is a pretty cool tutorial out there you can check out:
Nice job who ever took the time to do this!