I went with the Verizon iPad and for $100 bucks I took over a 3G unlimited data plan/line from a ladies family plan she was looking to dump. I purchased the Droid Razor off a buddy that didn't like the larger size and took the phone into a VZW store to activate the line in my name and get a LTE sim card.
Drove home, installed the sim card from the phone to the iPad. Unlimited LTE and a swappable sim card I can use in either devices. I have a secondary cell phone number and a plan that will be $70+ per month but unlimited data and the speed is faster than my AT&T uVerse 24mbit line, which I dropped down to 6mbit and saved $42 per month on that alone. 90% of my surfing at home is on my Ipad so it's rather awsome to not watch a meter. Worth every dollar IMO.
I don't use torrents, I don't intentially try to see how much data I can use. I do normal browsing, use wifi when I can (100mbps at work) and get to be mobile all weekend. If you have, or can find a grandfathered plan... It's rather amazing to have 12 to 25mbps speed on the go. I have yet to stream any video, from YouTube to HD movie trailer and have a single "buffer", it plays right away and is perfect. It really changes the iPad experience for me. The past wifi performance was not all that impressive, LTE performs well beyond my expectations!