I have a question that is not going to answer your question. lol. I went and watched an arab/half-arab show a couple of months ago and noticed that ALL of the hunt horses were in snaffles. Not a single one of them were in dbl bridles, or anything with curbs. In the morgan breed it is completely diff, only jr horses go in snaffles. So in the arabs is it a rule that you ride in snaffles?
Regarding your choice of saddle pad, personally I would go with the pad w/o the number slot if you are showing at a show that none of the other exhibitors are using the one you have posted above.