First of all, T-Mobile came up 1st or 2nd in customer satisfaction in all the reviews I found…Cingular was pretty much the opposite. Even my own experience with that. I spent 10 minutes on hold the two times I called Cingular, and I couldn’t get a consensus answer on what data plan was required. With T-Mobile, I was never on hold in 3-4 phone calls, and the sales reps seem to know their products.
As far as the SDA goes, it’s amazing. It’s runs Windows Mobile Smartphone Edition. (I’m a Mac lover, but still appreciate Microsoft products — now both sides can mock me.) I think this is the best product I’ve ever used from Microsoft. It’s still a little bulky here and there, but more simple than any other Microsoft product to navigate through. It has features that are well throught through and I have little difficulty navigating through the OS with one hand. Best of all, it syncs at regularly scheduled times with our Exchange server, so my email and contacts are always up to date. If you’re out and about, and especially if you use and Exchange server, this is a pretty special product.