The following is just general info for anyone, not necessarily a direct reply.

Any home router you buy today acts as a switch/hub in regards to its LAN-side ports and Wi-Fi. There's nothing special about this with regards to XBL, and TBH I am unsure what situation Orange Chikin would have been in prior to their current router which would NOT have fit this scenario.

In my experience, the difference between routers that allow multiple XBoxen to have open NAT vs those that don't is primarily whether they support UPnP, and whether they handle it well (if you're familiar with the concept of port forwarding, UPnP basically allows that to happen dynamically when the XBox requests it). Unfortunately, there's no good way to tell precisely which routers do without just trying some of them (you might be able to tell whether one supports UPnP before buying, if you're lucky, but not necessarily whether it does a good job of it). For what it's worth, I know from my own XBL experience that pfSense does a great job. It's admittedly a little more involved than setting up a typical router, but load it on an old PC and use that as a router if you're feeling adventurous.

So, aside from installing pfSense, here's two options I'd realistically recommend for anyone using XBL to help ensure open NAT:

1. Most desirable: Try to determine whether your router supports UPnP, and if possible make sure it is turned on (some do not enable it by default).

2. Less desirable: Enable port forwarding. The exact steps here vary depending on your network setup. There are plenty of existing guides out there on how to enable port forwarding for XBL, so you can look them up. Or shoot me an email if you get stuck and I'll see if I can help.

Note: I say port forwarding is less desirable for a reason. Aside from being more work to set up, it breaks if your XBox's IP address changes (there are ways to mitigate this pretty easily, but still), and it only works for one XBox at a time.