I never get more than 350-450 KB/s between MorphOS and Linux with the 68k smbfs over my 54MB/s WLAN.
With FTP I get 2MB/s across the same network to the same machine.
Well, I'll have to benchmark it properly. Certainly while the A1 still worked, smbfs between that machine and the linux box was close to saturation point on a 100Mb connection. For example, I used to run the SDK on the A1 and compile sources that were actually over the network on the linux machine. Transferring large files would hit 7-8MiB/s no problem.
With PCMCIA on my A1200, the speed is much lower and I don't think I get much more than ~500KiB/s for anything.