I'm not sure if this helps as 3g may not be fast enough for you but they are now offering 4.5gb (+500mb with auto-pay) for $40 for 3G. Hard to beat that deal!
Hello, I have noticed that from time to time when data doesn't work, I have to restart my phone and then it works again. Particularly at the start of a new usage period (for me it is the 13th of each month).