Wouldn't you just get a mobile hotspot? Or are you traveling to places with poor cell reception?
If you are in a Virgin Mobile (Sprint) 4G area with coverage - then buy one of their hotspots (used on ebay to save $$$), $5 a day buys you all the data you can eat & it stays fast. You can connect more than 2 devices. Save $86 a week.
Alternativly, get on Verizons pre-paid plan: $45 a month for unlimited voice & text, subscribe to auto-pay & you get 1GB a month for free. You can buy an additional 3GB for $20 - you have 90 days to use up the data, the use your iphone as a hotspot.
Virgin would give us around 1.7gigs per week at the $5/day. It would be more expensive at our levels.