Summary: I have been using a WRT54GL for 3 years running DD-WRT with absolutely no issues whatsoever. I was looking to upgrade my home netowrk to wireless N, and get a bit more range and speed, so I figured that this was a logical choice based on my good experience with the previous Linksys devices. I loaded the router up with the newest reccomended build of DD-WRT from their site, and it seemed to work as advertised, except that I had no range improvement whatsoever.
Summary: I bought this to replace an ancient WRT54GS whose radio finally failed, with the intention of putting OpenWRT on it. I was a bit worried since the OpenWRT wiki lists this router as a work in progress, but it turns out the recently released Backfire 10.03.1 works very well, and my router has been quite stable for about a week now. Installation was trivial through the OEM web interface.
Summary: Router worked ok for more than a year when there aren't many devices. When the device is fully populated, it can't handle it. Drops wireless connections, and even wired connection deteriorates. I expect these devices to work fine for definitely way more than a year.
Summary: I had been a fan of Linksys products for years, going way back to the first days of DSL, but no more. I bought this router and had pretty good luck with it (although it seemed slow) for a while. Then I started seeing huge performance problems. Slowly over a period of a couple of days, my bandwidth would degrade to the point where I was getting 300k/sec. When I reset the router, it would jump back up and then immediately start to degrade again.
Summary: When our old WRT54G died we decided to step up to a Wireless-N router. We've had this router for a couple years now, and also got an identical one for my parents, and have had mixed results with both. The setup and installation is fine but we have experienced flaky connectivity issues with certain devices on both routers.