I bough two different boxes I bought the Zenith DTT900 from HH Gregg and the Digital Stream DTX9900 from RadioShack. They pick up a few different channels and work differently. Most noticeably the DS picks up 2 more stations and has a higher quality remote. The Zenith has better looking menus and has a few nicer functions (the previous channel button brings you back to the last channel and brings up a menu of the last 5 allowing you to jump around quickly). The Zenith has poor volume (only control for the box volume) control while the DS has buttons to control both the TV volume and the box volume. The EPG (tv guide) on the zenith only shows the current and next show while the DS has several hours listed. While that is important the EPG is usually wrong, under the current daylight savings time everything is off 1 hour and not all channels use the EPG, some channels only have EPG during the day and not at night.

When people ask which they should buy I usually suggest one different than I have so we can trade the boxes amongst friends if we find ones that work better in our houses. Especially since I have friends who are buying them but don't need them.