I own one, Cingular 8525, not sure which HTC model that is, but it is HTC. I have had for well over a year and I have not a scratch on my screen, and it lives in my pocket. The HTC's are actually not really phones, more Mini computer with a phone, as it runs windows mobile.
As far as the quality, the phone is OK at best. It is a little sluggish at times, were the IPhone is very smooth by comparison
I paid 200 for mine, which at the time they were selling for around 500, i would say it was well worth the 200, I cant say i would feel the same way if I paid 500.
Ill add this as well, if you are gonna get it to primarily send text messages then get an envy or something like that, if you use outlook for business and windows scheduling functions then this may be worth while.