You don't need to have two different vendors to interoperate and get into comparability issues or inter-operability issues.
Fortinet FortiExtender offers seamless initial setup with centralized management and integration capabilities with 5G LTE modems and networks. It serves efficiently as an active secondary or backup link. However, troubleshooting can be challenging, lacking FortiGuard-like features, and requiring awkward SIM handling. Pricing is a concern, especially for 5G models. Future versions could benefit from a smaller mobile client footprint to enhance usability.