I have the6AL in my 440.My kid has the 6 that has the built in rev limiter.Both are flawless and he picked up at lest 3/10s when he changed from the MP in his 413.Price for dist and box is around 450 to 500.Id buy the 6 with the built in rev limiter if I had to buy another new box.Mine is 12 years old.Dist is super easy to set up also.Rocky