The MILLENICOM unit will give you 20GB using the VERIZON NETWORK but that additional 5GB probably not much help for you haha...
I have the VERIZON MIFI 3GB Dataplan original offered way back then and it is great for checking in with the kids, paying bills on-line and occasional surfing the internet. The killer for us a couple of time was the auto download of UPDATES until I figured out how to turn off the auto download part. Down streaming one TV show eats us up real quick with only a 3GB dataplan.
I will find a good WIFI hotspot when on the road and do my UPDATEs downloading...
Roy Ken