I had a mesh network before and it really sucked. You're cutting your Wi-Fi bandwidth in half or even more a lot of the time. I replaced the backhaul with MoCA and I'm much happier with it.
It depends on what gear you get. Some gear do backhaul over a different channel which doesn't cause reduction in WiFi bandwidth on the channel being used for end-user devices. E.g. some Netgear Orbi models do this such as the one I use at my home.
