Load balancing 2x WAN on same FTTH gateway

I see a lot of topics about load balancing multiple WAN, but has anyone have any experience with load balancing 2 FTTH (fiber to the home) connections from the same IPS and therefore probably on the same gateway?
I know routers from other vendors like Ubiquiti have problems with 2x WAN on the same IPS gateway.
And if one connection is 500/500mbps and the other 200/200mbps will I have a 700/700mbps connection?

Thanks

Mischa

Multi-WAN with same gateway works as described in this thread.
Regarding the resulting bandwidth, you will have 700/700-ish with multiple flows while one flow cannot be greater than the WAN link it is assigned to.
Look at the examples in this manual page.

-Chris

Same gateway address for multiple connections is possible with gateway=%.

Thanks for the quick response.

Mischa