the duratracs are a great all around tire.
but the load range of the MTZ would be better...
idk man, its a toss up. personally, unless you're towing the boat daily... i'd get the duratracs. in whatever size fits your truck.
33's and 4.10s with 4k of towing, may not be enough gear.. you may want 4.56's or 4.88's. that's a personal thing, i always like the lower gear option.