Is there an actual advantage to BBP vs SBP?

Best bet is to have hagerty roadside assistance or AAA. Its almost impossible to have a spare to fit both front and rear unless you have the same size all the way around, may be possible to get a tire thats in between the height of the rear and height of the front but then again unless you got a open diff any slight variance in tire dia on the back can cause some serious problems with a posi unit