After years of BB use, I've been using an iPhone for the last 3 months or so. It's a great device, but for business use on a BES it isn't close to a BB. The Exchange sync worked well enough, but it was missing too many features that I came to rely on.
Just went back to BB this morning. It's like having an old friend around again.
z10 on AT&T (plus an HTC One X)