. . we didn't have any Windows machines on the network,so I don't know anything about supporting them.

We used a 3Com LAN Modem (its actually a router but they call it a LAN Modem "for clarity"), a 3Com dual 56K router and a 3Com ISDN router. We also set up a Linux box with Dial on Demand. The biggest problem with these devices was NetBEUI, which causes them to dial frequently even though nobody needs the connection. InJoy filters this out with an OS/2 network, as do some of the devices, but we never quite got rid of it with the ISDN router or the Linux DoD box (though I'm sure there's a way). This was all years ago, and the devices have probably all been improved to handle this by now. If your network uses only TCP/IP, this is not a problem.