Aaron takes an in-depth look at the HTC Radar 4G, T-Mobile's first 4G Windows Phone and a nice mid-range smartphone option on the carrier.  Radar 4G packs a 1 GHz Snapdragon CPU, 3.8-inch display, 5-megapixel camera with 720p HD video recording capabilities, a front-facing camera (take that, Nokia Lumia 800!), and Windows Phone 7.5 (Mango).  It's available now for $99.99 with a new agreement.  Is it the phone to get this holiday season?  Part 1 of 2.