Have a customer with IPO R9 who wants to deploy remote 9608 phones for a few employees. Any recommendations on do’s or dont’s with this type of setup? I’ve not tried it personally yet.

Pretty straight forward.
Basically, you forward the H323 ports necessary.
Make sure that the extension is set to use remote worker and that all your remote worker boxes are set in System.

We have set ours up to use VPN authentication which seems pretty secure.

Got it working. Didn't have to forward any ports either. Just setup the customer's FortiGate firewall to allow VPN access, and setup the VPN tunnel on the 9608. Once the VPN was established and on the customer network, it found the call server and all was good to go.

Thank for the information and help. Appreciate it.