All,
I spent an hour on the phone with SonicWall. They had an issue with the 1b requirement, which is: route all traffic to the T-1 first until it is saturated and then all traffic after that is routed equally between the two Verizon services. For multi-wan routing, the SonicWall firealls have a) basic failover, b) Round Robin, c) Spillover and d) Ratio. But they are not able to "cascade" or combine these. For instance, route all traffic to the T-1 first is "Spillover". Then split the data into both of the Verizon firewalls would be Ratio. You can do one, but not both. This same issue occured with the Watchguard and it would be my bet that most medium-throughput (between SOHO and Enterprise level) firewalls will have the same issue.
It's looking like what we really need is a way to "bond" the two Verizon services to make them look...