Toyo Open Country ATII is what I had on my previous truck and what I have on my Tacoma now. Excellent tires, quiet and comfortable ride, long lasting thread and very good mpg compared to other tires in the same category.
What undercoating did you use? Just curious.
Btw, I have a 2016 with 37K miles on it and no rust at all. But I am in Florida, no snow here, just high humidity.