I can say while developing my script, Load Balance Mode when properly working (Using my Script), it will combine the 2 ISPs and achieve total bandwidth. I have a 1Gbps Primary WAN and 100Mbps Backup WAN and when running speed tests I would be achieve 1040-1070Mbps which is about the most I would get with both combined. That was with a 9:1 ratio configured, the problem with Load Balance Mode without my script is the stock firmware doesn't properly apply the fwmark rules in IPTables Mangle Rules so even if the traffic is being marked when egressing out of your network, the ingress traffic is not properly marked because of missing rules so sessions are broken. I resolved this issue with my script.
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