I am located in the United States. A client uses Optimum as their Internet provider and they have Optimum 500 which gives 504 Mbps up to Router and 540 up to Modem. Their router needs to handle 200 clients and I have AP's that can handle that number. They had a SonicWall installed and I want to replace it with a router that can handle the load. Suggestions?

The question is what everything needs the router to do. The 750gr3 could be enough on one side and ccr could have problems on other side.

I'd like the router to handle 200 wireless clients, email, streaming, etc.

Router doesn't handle clients but manipulates with the packets. So what everything you expect it should do with them?