I've just replaced a Touch HD (Windows Mobile 6.5) with the Desire HD as my first Android handset... I'm stunned. This is an amazing experience and I love the phone and the software. Two of the apps I've downloaded have crashed once but in every other respect the whole experience has been very smooth. It's definitely not 'buggy'.
Several things have given me the WOW factor:
- the way the phone interacts seamlessly and continuously with the Cloud, meaning my calendar and contacts are always up to date, maps are peppered with information, Google navigation includes Streetview scenes, searches include web-based information seamlessly and quickly, and Facebook updates are integrated in both directions.
- the app store (HTC Market) is a simple and effective way to get hold of software to reproduce the functionality of applications I'd bought for my WM phones in the past.
- the responsiveness of the screen to my touches is as good as the iPhones I've held in the past, with no lag whatsoever. That's a huge improvement over Windows Mobile.
- the web browser is amazing: quick to load and render pages, quick to zoom and rotate, and smooth in scrolling. A genuinely pleasant experience, even compared with the VGA screen on my Touch HD.
I haven't regretted the change from WM to Android and the Desire HD is a very, very impressive piece of hardware. I'd have no hesitation recommending it to anybody.
ETA: The proximity sensor works perfectly on my handset. The battery case doesn't close perfectly... but it doesn't bother me at all. (I probably wouldn't have noticed if nobody else had mentioned it.) The battery life is no worse than I was expecting - it's no worse than my Touch HD, even after only two charging cycles.