The S&S 124 is a very unreliable motor. It may run like a bat out of hell for a Harley but has a longer stroke which translate into a very short lived engine. About 50,000 or less mileage. The 111 S&S on the other hand is a decent motor which produces more power than the screaming chicken version. You are looking at about $10,000 for the crate engine plus modification to the primary and fuel system. With out the mods to the primary and fuel system you really have nothing but a accident waiting to happen. By the time the fat lady sings you have spent around $15,000 dollars for a bike that still will not outrun A rocket X completely stock. A few of my friends who own such bikes found this out the hard way. My Harley which has a lot of modifications to the engine and is considered very fast for a Harley can not hold a candle to the Rocket. With that said I really have nothing against Harley's. I kind of like the Harley's just do not care much for some of the morons who ride them.