HTC SDA (USA) / SP5m (Tornado)

That's a good question. But before you do, you have to consider the following: price, durability, overall quality, personal needs, and the shelf life of the phone.

I have the SDA, and personally, i believe that it is a wonderful phone. I researched it for about 2 months before making the jump, and i wont look back. I purchased it the first day it was released, so I got my money's worth. I have dropped it twice, once on the face on cement, and i only have scratches on the phone, not the screen, and once in walmart, and it didnt leave a mark. A friend of mine dropped his MDA once and it broke the screen.

You should consider what you will be using the phone for. For example, the MDA clearly outshines the SDA with respect to text messagin...
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I also chose the SDA over the MDA and I couldn't be happier! I really like how durable this phone is. I've had it since March and I use daily and it's in near perfect condition (a few minor scratches that were my doing). The Wi-Fi works GREAT, the EDGE/GPRS is really good, although it does lag from time to time, and e-mail is a breeze. I text, e-mail, surf the web, and use the phone features on a daily basis and I can honestly say I can rely on the SDA for quality and efficiency. I've gotten used to using the small keypad, which almost lead me to the MDA originally, and I wish they would make the "joystick" a little more comfortable feeling, but that could be just me. The screen is great, the camera is good, video and MP3s are awesome, and t...
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Dido on the SDA. Ultimately it came down to reviews that said the SDA had better reception than the MDA.