In a class A you are better off to carry a little used credit card and a Coach NET membership or something like it (Roadside assistance)
If you pop a casing a mobile tire guy can be summoned to fix it where you stopped.
In fact if you have 22.5's and you take it to a tire store they will call in their mobile tire guy to do it. May happen with 19s as well.
22.5 inch spare will not fit in my workhorse.. 19.5 would but I have the 22.5's 2200 and change of 22.5's as of last month when I put on all new rubber.