I have a generic one but off Ebay, bought for about $140 that works flawless on my 19' Redeye, just use it to quickly change throttle sensitivity here and there depending on driving type and mood. I tune my own car and have looked at the Demon ECM file and don't see anything that would cause codes by using one of these devices. There isn't much difference in the majority of the Demon file vs. Redeye f ile.
I honestly don't see where this device could possibly make your car run faster at the strip. About (5) of us race hellcat variants here weekly and know these cars well, any of the throttle enhancer products are going to make the car "feel" more lively on the street and do have a very positive affect on the driving exeperience of a stock car since stock cars tend to be "soft" in throttle commands; however, none of these products make the car faster and/or will result in lower ET's at the track.