4 inch drop? I really hope you're getting some custom rate ground controls, like 550+lbs...If not you will bottom out like there's no tomorrow. You also might want to get the GC extended tophats, which only work with koni shocks I believe. On the other hand if you really want a 4 inch drop you will need to get pretty stiff ground controls which means you're going to be pushing the limits of what the OTS Koni's can handle. Oh and you can forget about comfort with a 4" drop.
I suggest you reconsider your ride height/suspension choice.