I would assume it would be fine. You are basically doing the same thing as shock spacers. The only thing I can see that it would hurt would be your pocket book for the shocks. Remeber that just because you can turn the preload up on the aftermarket shocks, doesnt mean the shock is longer. If you run the shock at near its longest position, it will be topping out , and making your ride and handeling awfull. You would need a longer shock, not just an adjustable one. By using the shock spacers, you are keeping the shock travel where it is supposed to be. Hope that made sense.