i use this on my dob 08, though it doesn't eliminate flex completely it does make a difference, its relatively light thats why i went for it as a 2 bolt booster, im sure a 4 bolt will be a lot better, but to be honest this set up i've got seems fine. and the spacing is funny on the dob frames, mine didn't measure 100mm, but around 98mm, so i had to file it a little, but its fine and it does look the tits. hope i've helped steve