I m planning to buy either Sprint overdriver 4g or MIFI for personal hotspot. I like the thing that it is not device specific so I can use it with any device I carry that time. The only thing I didn’t like is the battery life. I read that it is not very good. and I travel all the time. Has anyone of you used these both? There are advantages and disadvantages of both. Please help me make a choice. I like sprint data plans and verizon plans are just not of my liking.