I have the large Agri-Fab tow spin spreader that holds approx. 120 lbs. that has to be 20 years old. Still works great, but the biggest problem right now is the tires are pretty much shot. Even though it's kept inside when not in use, the tires cracked, and lose air pretty quick. Not fond of the plastic wheels either. But, I now see the newer ones have have steel wheels, and should last longer, and be better if the tires ever need replaced. Too bad they didn't go ahead and make the 2 piece rim, to make life easier.
I'll more than likely replace the tires on mine this year, but will remove the old tires before ordering new ones. My gut tells me those plastic wheels may crack/break. Just going to have to be careful... Otherwise, it's been a great spreader.