I've decided I am going to put tri-ribs on the front, that is a given, but what are your thoughts on rear rubber? I was thinking of putting a set of R4s on my 444 as I have seen how they fair on my fathers Kubota. I know there is obviously a good size difference between the two machines, but the heavy Japanese tractor has yet to do a number on his lawn after 6 summers. Do they make a decent R4 tire that will fit the stock 16 inch rims? What are all your thoughts on R4s in comparison to Ags?