I'd stay away from Fords. Chevy's 5.3 is a great engine, very reliable and great gas mileage. The 6.0 is a fantastic engine in regards to power, and while it loves gas, I do hear its a lot better than the dodge 5.9. I have had problems with my 6.0, getting this multiple misfire code from hell all the time, the truck runs fine though, i hear its pretty common and hard to get rid of, I've replaced a lot of things trying to get the damn light to go away, no such luck but it runs decent and plows and tows like a boss so i guess i can't complain.
btw, I'm right down the northway from ya Jay. If yer plowin up there, I think you'll definitely want more power than the 5.3
In reguards to your multiple misfire have you tryed a crank re-learn ?