Like and iPhone
I expect that the HTC's are probably about the best out there, given that they make / made a lot of the Windows Mobile devices for so long for folks like HP etc.
You will have to decide what you want from the device. Wow-factor = iPhone (I think anyway), Sim-free = most anything else at this stage. My Nokia E61 has 3g, WiFi and GPRS so it pretty much does it all but it does have a relatively small screen. I have had HP iPaq's (never found one I liked), Nokia's (N80, E61), Sony Ericssons (P900, P910) all very good in their own way but all just different enough to have their very own pro's and cons. (Company was testing them and we ended up with the Nokia's while I preferred the Sony's because they had brilliant battery life - days & days vs days for Nokia and hours for the iPaqs)
I'd suggest you either wait & play with each one a bit or make a decision & lock yourself in.