I have been using an AT&T MiFi for almost 2 years now and have been very happy. The Winegard system simply moves the MiFi to the roof and adds some better antennas so performance with that setup should be substantially better than my MiFi sitting on my dash.
What I post is my 2 cents and nothing more. Please don't read anything into my post that's not there. If you disagree, that's OK.
Can't we all just get along?