I had a single, went to the dual...noticeable difference in acceleration...but, a single is better than none at all...I don't like the plastic hangin' on top of my engine bay...I like to see the engine, and I like getting the hot air out asap...so, I hung my engine covers on the wall for wall art....took the drip pan off both cars...they might make a good kiddy sled in the winter time...lol....just my preference...each to their own...but amg engine should be seen, not hidden...