Thanks, Mark and Christian. It looks like I'll be trying the Asus router next. I'll start with the stock firmware and go from there.

I just hooked up the TP-Link Archer C5, but it doesn't have any sort of "media bridge" or "client bridge" mode. So then I looked around to see if any of the firmware replacements supported it, and HEY! no they don't. Looks like they supported v1.2 but apparently they switched to a Broadcom chip in my V2 product, and there's something about licensing blah blah it's not going to work.

I'll keep this one to sell to a client but now I need my FOURTH device. This is just insane. I keep thinking about how I had a wireless bridge over ten years ago. I guess that in this day and age where everything is wireless already, it's a much smaller market.