I don't have a phone I can tether to, so I got a Clear Spot personal 4 G hotspot and I've got a fantastic signal everywhere I've tried so far in Boston. Seems I'm surrounded by their towers. Now I'll never put this tablet down...I'm addicted.
My wife and I got the Sierra Wireless Overdrive from Sprint, 4g/3g. Right around where we live it's unbelievably fast thru 4g, 13mbps downstream - .8 up. Can network up to 5 devices via WiFi (B/G)at once. We use it on the road to access web, etc with laptops, notebooks. We recommend it to anyone and everyone. At least anyone and everyone who have Sprint, not sure who else carries it.