So about a year ago I decided to try the Dynamod HEI module that came with my DUI distributor. The Delco one that was in there was doing ok. But I read an article that said the some aftermarket "performance" ones were worth a little power at higher RPM. Didn't really notice anything (Yeah, I know...why was I not surprised?... lol). So I just left it in. Last few drives I started noticing power starting to fall off above ~4000 rpm. I knew the fueling was always right on the money, so I started back tracking what the latest things I did and realized the HEI module. Put the Delco one back in and voila... power came right back. Even the start up is snappier (guess it was degrading). I use this Arctic Silver thermal compound under the module and it was still nice and fluid, so I know the heat transfer is good. Must just be the same-ol' same ol' with these unreliable aftermarket stuff. Guess I'm glad it didn't fail outright and leave me stranded.