well, i had two of the chinese procomps for about a week before the supplied harness melted to itself, and the driver side bulb went three times in that week.
the 20 buck ones didn't give me any problems.
i had a bad experience with procomp, 4 wheel parts fixed it up for me, but pro comp hotline didn't want to help me at all try to find out what hte problem was, so i cant really speak for any other pro-comp lights.
the KC's have been great too, they were 100 bucks more than the procomps i had, but well worth the money.
if i could do it all over again, i would have sealed the 20 dollar lights with the upgraded bulbs, or went ahead and saved my money on the KC lights.