My experience with a number of Class A gas motorhomes over the decades is that with the alignment set correctly to whatever the specs call for in maximum positive toe in, the RV will track MUCH straighter on rough roads and crosswinds but you will see more wear on the outer edges of the steer tires. Many years ago I complained to a front end shop about the wear on an old "Flying W" Winnie and they took some toe in off. The difference in steering was noticeable and bad. Had it put back to spec and just resigned myself to replacing the fronts sooner in exchange for better tracking.