If you've never seen the 4th, then if you can handle the crowd I'd say MK. It's one of those things that you want to see once, but it is a madhouse. Since we've already done it, we now do Epcot. We were there last 4th of July. We got off FEA at 8:45pm and still found a great viewing spot on the bridge heading back toward FutureWorld (just past Mexico). So we waited all of 10 minutes, not packed in like sardines, and the show is spectacular. Oh, and we had the added benefit of being on the bridge, so once the show was over, we had a head start on the rest of the crowd leaving.