We also use a Verizon Aircard and have been mostly pleased with the service, BUT, there seem to be two networks, the "National Access" broadband network, and the "Extended Network".
We have found that the "Extended Network" is slower than the worst dial-up we ever had! The "Extended Network" is not just for places in the boonies. We were put on the "Extended Network" in Oklahoma City and Hagerstown, MD!
My point is that your current slow service may be a result of your being in an "Extended Network" area and, if it is, I don't believe a booster, which will only help make the signal stronger, will help, i.e., it will only make the slow "Extended Network" signal stronger, not faster.
Good Luck! We'll be interested in other comments and suggestion which you get.
Don and Mary Ann (The Navigator) Nesbitt
Cary, NC