Comment Re:The answer depends on the fine details. (Score 1) 180
If you're going to recommend a pair of Cisco routers, then why not run GRE over IPSec? You can run EIGRP over the tunnel interfaces, and configure either equal-cost load sharing across the links, or use variance to proportionaltely allocate traffic over the links according to the expected bandwidth.
If you want to keep some conversations pegged to a particular link, you can policy route those host/network pairs, while still maintaining failover if that link dies.
You don't even need NAT/PAT in this scenario if the private address ranges don't overlap.