I'm using one of the cheapies on my 20D as well and have had np so far. Even gone so far as to get it modded so that I can plug my serial to 2.5mm 300D computer controlled bulb cable into it.(try saying that with your mouth full
) I can now operate the 20D from a number of programs hiccupless. If you are a bit nervous you can get the whole setup including the TC80N3 and a serial cable from Hap Griffin from Shoestring astronomy. (he uses a 3.5mm plug for the conversion though so you can't use his 350D remote cable)