Thank you for all of that. That is great info! I guess I just figured I should replace it before it goes out because it is 6 years old now and my other one didn't last that long, and I figured a better one might have a slightly better range to cover the basement, although this isn't too bad. So as far as the numbers go...the Asus I have is 1900. So does that mean theoretically, it can transfer files on the local network at speeds of 1.9 gig? If I get other routers for access points, do they all have to be the same number or will they just work at the speed of the lowest one? If I am getting wired internet speeds of 900 right now, how come I don't get that same wireless speed when I am right next to the router (I just did a speed test on my phone right next to the router and got 550)? Of course that is plenty fast, I am just wondering why it doesn't get the full speed.
That makes sense about the POE access points too. Now I see the difference. I guess that would be nice to just mount that on the ceiling in the middle of the house, but if regular routers serve the same purpose, I will do that for now. Maybe when I remodel someday, I will run some cabling to install those in the future. Will the electronics interfere with the AP? If not, it will be great to just put one there by the TV because I already have a switch there so that can just replace it. And the other room has an ethernet port kind of hidden behind some shelves so I can just put there and it will be hidden too. I know how you said mesh is not good because it is just like a repeater, but what if you connect the mesh systems to an ethernet port? Will that get full speed like a regular router, or are there disadvantages to that? I am just thinking that you can get like a 3 pack of TP Link Deco for a decent price, and they look a little nicer and are smaller if you have to put them out in the room.
One more thing. The modem I just bought (Arris S33) has a 2.5 gig port. I know that is overkill, but Xfinity keeps increasing their speed so just to take advantage of it and for the future, should I get a router with a 2.5 gig port? The access points probably don't, because since my house is older, I believe the wiring is just Cat 5 to the areas where I am going to put the access points.
You don't need actual AP unless you want to say power them over ethernet. Almost any modern router has a AP mode and it gives you the advantage of having extra ethernet ports in the remote room and not having to use a switch. Real AP generally only have 1 ethernet port.
Then again you can mount a AP in the center of the ceiling where there is no power if you want.
If you are going to buy something better that your current router look at wifi6e. Unfortunately these are still pretty expensive but at least there are more models that silly $700 routers. Wifi6e should get to be very common it is a required feature in the chipset that supports the latest intel cpus. The boards will have a wifi chip or a m.2 slot.
How well wifi6e will work we will see I guess. The main problem with normal wifi6 was there was not enough bandwidth on the 5g band. They had to do stuff like run on the same radio bands as weather radar but if was detected they have to stop. The complexity of this lead to many vendors not supporting 160mhz radio channels so it didn't run any better than wifi5 which can also use 80mhz bands. Wifi6e runs on the 6g band where at least for a while there is enough bandwidth for you and your neighbors to have 160mhz to themselves.
In general it depends on what features you actually need on your main router. This is all a software thing which only you know what features have value. For the AP you need the simplest routers you can find. All routers with the same "number" will more or less perform the same. There are only a couple of chipset manufactures and all the router manufactures buy the same chips so the wifi itself will not be that different.