Waste of money, IMNSHO. Most folks that have problems are the ones that start screwing with stuff that they have little knowledge about. The worst thing you can do, IMO, is to read internet forums regarding engine mods and start trying to emulate what you read. Adding chrome and comfort accessories is one thing, but generally when shade tree know it alls start screwing with their engines, that's when problems start. The companies that sell that stuff is going to fill your head with all kinds of crap. Why? Because they're to sell you something. The **** thing puts out more horse power and torque than you could ever use legally. Why screw with it?
Just my .02 worth...