Disadvantage = void the 2-year warranty

---

Added on March 5, 2010, 5:35 am
All three models can do what you've mentioned (with 3rd party apps in some cases). If you need more functions, HD2 (WinMo) is the best. Milestone (Android) and N900 (Maemo) cannot install Garmin MXT (unless you prefer other GPS clients). HD2 CPU is 1GHz with big 4.3" screen suit your desire of watching videos/series. FYI, I primarily use HD2 with the same objectives as yours...lol...

---

Added on March 5, 2010, 5:36 am
"Big" 4.3"...... very very very...naughty....lol

i dont think you are able to do video streaming with HD2. apart from built in youtube app. i've tried downloading some 3rdparty java/flash app, and even tried using different browser but it doesnt seem to work. and i'm not too sure about winrar . havent try using it on my phone.
one thing i find quite annoying if i try to do my work on my phone is because it lack of keypad. example, although the screen is huge, but once you open the excel file, and try to type in it, the keypad takes half of your screen size already. but its my first touch screen phone