Cane Creek IS2 Headset - Upgrade?

When I was building a frameset and got to putting together the front end, a gap was left between the top of the headtube and the top seal of the headset (ie - the bearing seated in the top tube sat up slightly and the top part of the headset did not come down enough to cover the bearings). The headset is a Cane Creek IS2 - from other forums i've read this is a common issue with no apparent solution. I dont know if it was a design flaw, but I dont really want dirt or water getting in there. Does anyone have experience with these headsets? Would I have better luck with a different company?