My volume button came clean off on Saturday, and 3 wouldn't replace it as there were some marks on the rear. I dropped it from my lap getting out of the car with its dot sense case on, and I have to say as an ex Iphone user I was amazed how easily it got damaged.
It looks as good as an IPhone cosmetically, but is comparatively not as we'll made. The dot sense case is quite good in operation, but even from 2 feet up offers no protection whatsoever.
I've sent the phone back today to HTC and I'll see his much they want to replace the volume key(which was already loose before it was dropped)