Dynamic Routing between Palo Alto and WatchGuard?

Hello networking!

Does anyone have any practical experience with multiple IPsec tunnels between a Palo Alto cluster and WatchGuard cluster with ospf over the redundant tunnels for ECMP? Going to be a hub and spoke design with the several WatchGaurd sites connecting back to the datacenter Palos.

Need to connect two segmented parts of a client's network (they purchased a company), and do not have the means to try this in a lab environment. Would rather not POC this in production, and spending money to re-architect their WAN/rip out the WatchGuard for Palo Alto does not appear like an option right now.

Thanks!