I had the Stealths...don't do it...he forgot to mention that I told everyone to mill .010-.030 off of the bottom of the heads because they are not flat...they don't have a good straight edge in china...others had had broken valve guides...you have to **** can their springs, lock and retainers and go with double springs, 10 degree locks and retainers...save up for the eddys and you won't be disappointed...I was able to take the eddys out of the box..change the springs, retainers and locks with 10 degree ones...7 and 10 degrees are totally different...I checked mine with a good straight edge and bolted them right on with no...no...no..problems....both could use some street porting or CNC porting...the eddys come with 84 cc combustion chamber and the Stealths come with a 80 cc combustion chamber, those are the major differences..