The WRT54 is dog slow by today's standards. My residential Comcast service is faster than it can handle; my max down almost doubled when I swapped my WRT54GL for an AC3200
A few years ago I used my 54G to DL a 15GB file at (a reported max of) 60Mb/s. Obviously took a while ... without hiccups. I'm guessing most US customers aren't getting service that fast ... so there's still plenty of use for them. (Still use one all day at 25Mb/s.)
At least get a WRT841N, they are like 15$+sales tax, unless you get the wrong vendor. Less if you find refurb's or buy bulk. They are the main workhorse for our local mesh network, with WRT1043 devices handling encrypted uplinks due to the lack of speed with chacha/poly running on the former (think under 10Mbit/s). Don't worry, they do handle advanced mesh routing algorithms at line rate, e.g. 2x2 mimo 802.11n and 100BASE-T (4+1 ports).
E.g., they handle mesh domains of about a thousand nodes before one needs to split, and mostly due to L2 traffic starting to hog the slower links (it's an L2 mesh).
Thanks, I've only got 1.5Mb DSL, but that's a better price point and I appreciate your useful comments on mesh.
At that speed, and if you won't need fancy buffering and got the necessary 3.3-ish volt ready, check out some esp8266-based mesh/repeated tech. Possibly with using wires on their (quad-) SPI bus to pair two, potentially over quite a sizable line length. Saves airtime.
A cheaper, and better (longer 5ghz and 2.5 ghz) option is the Archer C7 router as well.
The problem with that being a lot of people's internet is now faster than 54mbit
802.11g actual max throughput is 22Mbps, assuming you don’t live in an apartment.
It's usually 802.11ac
EDIT: oops, thanks
I think you may have misread something: he's stating that the WRT54GL router which was recommended a few comments above, only supports up to 802.11g.