Last time I replaced the tires on our 16ft
Scamp, we had had a blow-out near Crescent City, CA. and were limping on a suspicious looking old spare. I was hoping to upgrade from the 205x70-13's on the trailer, but the closest size they had in town was 185x80-13's in a car p-metric carcase. So I really had no choice but to use what was available or wait several days, this being a Friday before a holiday weekend.
Anyway, these Dayton 185x80's have worked out great for over five years. We have kids in Missouri and California and normally winter for several weeks in Texas each year so I'd guess they have more than 50K miles. The tread is about 1/2 worn out, rounded quite extensively on the edges because of their being used near, or possibly even exceeding their
weight rating.
So I'm thankful for my good luck but probably shouldn't press it much longer. An upgrade is in the works. If I can, I will go with 6 lug 15's that will also mount up to my tow vehicle. Might even get ambitious and make fender flares to provide clearance for some 31x10.50-15's!