The Linksys PSUS4 print server is NOT compatible with Macs. Macs will not discover this server, in my experience. I bought it so that I could have one networked printer. The printer itself, an HP DeskJet F4240 All-In-One is compatible with Macs, as I've got it plugged right into the iMac and it prints without issue with no configuration and it is auto-detected. When I add the print server into the mix, things get bad. The server also appears to overload quickly, requiring constant power-cycles. It prints fine with Windows machines, though.
I've left a review at NewEgg ( search for "unixfool"...currently, the review is on page 1) but this was before I tested on Macs.
Tried it for Linux also (gOS on the Dell Mini 9)...it doesn't like the server either.
If your house is heavy with Macs, avoid this print server.