We Setup a Checkpoint Firewall onsite which was behind a Balance 310 talking to a Checkpoint at the data centre. (Checkpoint - Checkpoint via the Balance 310)
Didn’t use VPN as found it to be a very inefficient way of doing it.
We did have to forward about 20 ports for the Checkpoints to communicate with each other though!
In in order to get a full benefit of the Peplink devices you can do the following. Have the checkpoint devices behind the Peplink devices from each site.Create a Speedfusion between the two peplinks so you will benefit from the troughput of multiple connections and high availability and create your site to site VPN tunnel between the checkpoint devices. This is a tested scenario with no issues.
If if you have on one site a Peplink and on the other site a Checkpoint device follow the documentation on the Checkpoint support site for site to site between checkpoint and Cisco. The configurations are the same.