site to site ipsec between F5 and CHECKPOINT

This might help:

Configuring IPsec between a BIG-IP System and a Third-Party Device

https://support.f5.com/kb/en-us/products/big-ip_ltm/manuals/product/tmos-implementations-11-4-0/19.html

and

https://support.f5.com/kb/en-us/products/big-ip_ltm/manuals/product/bigip-ipsec-interop-matrix.html

ps

I can confirm that it's possible to create an IPSEC tunnel between a F5-BIG-IP and a Check Point firewall. I've been testing this in my lab with R80.10 and it's working. I've noticed that it is key to use PFS in Phase 2. Without PFS in Phase 2 it didn't work. Here are some settings I tried:

Phase 1:

SHA-1/AES-128 + DH Group 2 works!
SHA-256/AES-256 + DH Group 2 works!

Phase 2:

SHA-1/3DES + MODP1024 works!
SHA-1/AES-128 + MODP1024 works!
SHA-1/AES-256 + MODP1024 works! 
SHA-256/AES-256 + MODP1024 works!