Well I have had the radioshack converter for a while and I also have problems with when it come to repeating sertin motions and repeatedly presing a button. I have also done a test that i made up, what you do is go to the controler menu and press a button repeatedly and you will see it blinking red ten that after a few seconds it will pause instead of blinking red then continue. Its a cool converter for lets say super nintendo but for fighting game i doesnt cut it. Its not acurate. I play GGXXreloaded for pc and as well as other emus and when I for example play with Sol Badguy and do his special qcb,f+hs over and over it doesnt happen too much with the radioshack converter. I did some research and found a solution. I bought this
It works like a charm
and its cheap
The BNS Single PS /PS2 Controller to PC Link Cable is cool but its throgh a parallel port. The driver i use is PPJoy v0.83. What i like about this converter is that it supports multitap but a havent tried it.