If USB doesn't work out for you then try buying yourself a Parallel Port Adapter
http://www.buynshop.com/productinfo/45/VG-PS-PS2PC4/
It might look like crap but I bought one and the reaction timing is even good enough for me... which means it is either instant or beyond my ability to see/notice it. I do speed runs on Super Metroid with this thing (42 min 73%) so it is definitely nice. I and my friends also use it with the Cobalt Flux and it works perfectly with SM and other things like this. Though the drivers run with Direct X (I believe)... but that shouldn't be a problem. Should you decide to purchase this (it's only $4, lol) then you should use PPJoy, as it is an excellent and easy to set up driver for this adapter.
http://wcarchive.cdrom.com/pub/simte...PPJoySetup.zip
Let me know if you have any luck with the USB or any questions about the Parallel Port Adapter or its drivers. I've used it for a long time so...

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