I hear this has a low priority for fixing.

The the work around is easy, but it takes hours to find it. Try searching google for "WPF radwindow does not maximize" and nothing comes up as a solution. Once you know that its cause you didn't set a width and height you might be able to find the solution online, but by then you don't need to search online anymore...

I found this on my first day of a trial and I spent hours trying to figure out what I'd done wrong. I've only got so much time allocated to evaluate your trial, and each of these "easy to implement but hard to discover" work arounds are quite costly.

I think Telerik should consider time wasted FINDING a work around, rather than just how easy the work around is to implement ONCE YOU KNOW IT.