I guess it depends on what you're doing with your Expedition. I ran BFG AT's for years, best tire for the street in the 90's in my opinion. When the KO's came out I the price went up and I went to bigger tires. I switched to Super Swamper SSR's. Once I got back to something with smaller tires, my '04 Expedition, the BFG AT's were unobtainable due to cost. I tried various tires the BFG Long Trail Tour were decent and the last 4 sets have been General Grabber HTS. I drove the Expedition with the Long Trail Tour and Grabber HTS both in more 30" of snow multiple times and 1/4" plus freezing rain several times as well with very little trouble, passing almost everything else on the roads. I have to go to work regardless of the weather. So I certainly can't say I need the AT's anymore, street tread tires are very nearly as good.
I can afford the KO's now days, but aside from the appearance I can't see a reason to get them. They cost more, are a bit louder and my off-road these days is fields and gravel roads. No more rock crawling or muddin.