Not sure where you have looked, but 3/8 braided stainless compression is very available and only a couple of bucks more than your other choices. For me stainless is the only way to go.
: I would like to know what type of sink hookups I should use. Braided stainless steel is not available with a 3/8 compression end (to fit with my angle stops) as far as I know and are quite expensive. I have read that some types of hookups can fail and cause massive water damage, although I'm not sure what types. The question is whether reinforced white vinyl is safe to use or is engineered polymer braid better? Is a PB flexible hose better than either of the others? What would be the best choice?