The Wesstell 6100 series is the standard DSL modem that is sent by Verizon for most DSL customers. The problems start with the fact that it is not just a modem, it also acts as a router that can only route to one device. This makes the "modem" very difficult to configure for use with a standard router.
The average home computer user with a decent understanding of how to follow instructions is not going to be able to configure any set up that will be functional in most homes. Because of this the cost of this "free" modem is significantly higher in tech support charges.
Additional draw...