How about the HTC Wing, which replaced the MDA on T-Mobile? Here's the review: http://www.mobiletechreview.com/phones/T-Mobile-Wing.htm . It's running WM6, is faster to reacquire a signal, but it's not much faster than the MDA.
As for the E90, phonesource-usa.com and importgsm.com tend to have fairly low prices on their phones and they're reputable. I think phonesource-usa is out of stock at the moment though. Apparently Nokia can't keep up with demand for the E90, and that's keeping prices high and inventory low.
-------------------- Lisa Gade Editor in Chief, MobileTechReview