I had a LinkSys wireless router and got rid of that one and replaced it with the SMC. I am a cable modem user in a wooden structure house. I did keep the LinkSys PC Card (no compatability issues. Haven't used WEP though)The device works great. Advertised range is very optimistic. The web pages load faster than the LinkSys. It has the parallel print server and serial port (for those not yet on broadband or who want a backup).
The only complaint so far is that the LED lights are recessed, so they are invisible if you are not looking at the device headon.
I do like how they put the ports on the back instead in the front like their previous wireless router. Also the rounded style is an improvement over the very plain, boxy old one.
The presence of only 3 ports may be an issue for some people. Or it could be a justification to get a PCI wireless card for that fourth PC. (glass is half-full/half-empty). Also, there is no dedicated uplink port (not a big deal if you have a hub w/ uplink or crossover cable). The adapter is substantially blukier than the one in the Linksys package. But you do get a 10 foot cable in the box.