I use PC2Amiga via Parallel cable now. It gives me speed about 40KB/s which is not that bad. The computer shop didn't have parallel-parallel cable, so I bought two Parallel printer cables, cut them and built one Parallel-Parallel cable, after consulting PC2Amiga manuals how to connect the wires. It took me some time though, to figure out which colored wire is for which pin number, and used a speaker for this. Before that I used NetworkPC which is the commercial version of PC2Amiga, and comes with cable, but I didn't have the cable, so I used serial cable which gave me a speed of about 8KB/s, which for small files was ok, but for the big ones was a nightmare.
One strange feature to me is that transfering files from the PC to the Amiga is slower than the other way around, despite the fact the PC is much more powerful (through the serial and the parallel conection as well). Not sure why this. Also you can't browse the Amiga directories from the PC side, but that's not a big problem, since you can copy files to the PC from the Amiga.