I guess it depends on what's important to you, Andy. Yes, there are issues with Diana (RWS/Umarex is just the importer), but then, there are sometimes issue with even a TX or Beeman. Truly, despite all the hoopla, the plastic trigger is a non-issue, IMO. Yes, they tend to ship fairly dry, but then, they don't diesel out of the box, either, so you don't tend to get burnt piston seals. Yes, the barrel droop can be a pain, but it can be dealt with. It's not at all uncommon, even with Gamo's. The major scope issues are much more an issue with the magnums like the 350 and 48/52/54, the medium powered guns like the 34 aren't as much hassle.
What it all boils down to is, how long do you want to keep your rifles? Trust me, if you've never handled one of the German rifles, you're in for a different experience. I've owned three Diana's, 2 rifles and a pistol, and there's no question these are a giant step up in quality over a Gamo or Chinese gun. These, like the Beemans and a few others, are rifles that will last for years, provided you take care of them, and will probably just get better with age.
So to answer your question, yes, I think they really are that good. And if the plastic trigger really bugs you, just wait until mid-year. The new T06 trigger should be out then, it has a metal trigger blade, and fixes some other trigger issues about the T05 that have always bugged me. And best yet, it will be a drop in replacement if you happen to have a T05 rifle! Later.
Dave