I just received mine, and could not be happier. I know it varies by provider and location, but I have had all three at my residence and Sprint is the first one to be clear as can be. ATT was terrible, I had to go outside half the time to keep it from dropping. Even Verizon had issues here. The Sprint has been solid.
I even had to deal with the hassle of keeping the same number from cingular and I had few real issues. It took a couple phone calls, but all in all it was not that big a deal. Using the temporary number they gave me this thing fired up and worked like a charm right out of the box. My E-mail push worked with no issues at all. I am having some tethering issues but I am pretty sure that is the PC (working on that in another post).
I came from a Pearl and I really like the larger screen, and the fact that BB Maps works with the GPS without an extra cost. It is very early, but so far it has been a really good move for me.