Last month in March, we looked at the unlocked version of the HTC HD2, one of sleekest smartphones in the market. Today, we look at the HTC HD2 for T-Mobile, which offers similar features with a few differentiating factors. The HTC HD2 packs Windows Mobile 6.5 at its heart, and if you thought you couldn’t upgrade to Windows Phone 7, that turned out to be inaccurate. Unofficially, you can upgrade it just fine, and that makes this Windows device an even more attractive option for Microsoft enthusiasts.

CNET writes, “The HTC HD2 boasts a gorgeous 4.3-inch capacitive touch screen, and T-Mobile preloads the smartphone with a ton of entertainment extras to take advantage of the display and 1GHz processor. The 5-megapixel camera takes excellent pictures, and call quality was decent. HTC Sense offers a more user-friendly and customizable user experience.”

However, “The HD2 is clunky and big. It runs Windows Mobile 6.5. We also experienced data connection issues and the smartphone felt more sluggish compared with the unlocked version.”

In conclusion, “The HTC HD2’s size and older operating system aren’t ideal, but you won’t find a more powerful or entertaining smartphone in T-Mobile’s lineup.”