dahkota - we are almost the same as you except my DROID does not tether. Had to get the MIFI unit to do that. It actualy worked out better for me in that I can have up to five of my wifi enabled devices working at same time. Also in the early days of using tether mode it tied up the cellphone.
Understand the newer cell cellphones doesn't get tied up when in tether mode...
My VERIZON bill is $248 a mo for two smart phone accounts, one standard cellphone account and the MIFI 3GB dataplan account. It appears I will be seeing a $40 increase depending on what VERIZON will want to do about my grandfather MIFI 3GB account.