We use the VERIZON MIFI 3GB grandfathered-in 3GB DATAPLAN for $30 a month cost. Just barely allows us to check our emails - check-in with the kids - and pay some bills on-line. Will get in some internet surfing but have to watch it close.
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Not able to downstream any video movies or TV SHOWs as they usually eat up around 1-2GB an hour...
There are some 20GB plans available but most all of the carriers now is cutting back on data when you start using a large amount. Using large amounts of DATA is getting more expensive now even if you can find it...
Just read on here today that VERZION is now going to cut back on their grandfathered-in accounts.
VERIZON seems to be the best carrier for us especially for those way off the road places we like to go to here on the east side of the US. Anywhere our Verizon Cell Phone setup work the MIFI unit will also connect and create a WIFI HOTSPOT for up to 5 of our WIFI enabled toys..
Good luck
Roy Ken