You might enjoy reading http://www.tedunangst.com/flak/post/technical-debt-and-tacki.... To address your points:

> Fun fact: Wasabi has more unit tests than FogBugz.

> It’s fully debuggable in Visual Studio. Breakpoints, variable inspection, single stepping, the whole enchilada.

But the whole post makes it clear that working in Wasabi wasn't nearly as difficult as you think.