I do like 3M micropore surgical tape in my FAK.
HOWEVER
I also find that most cases of blisters in shoes are due to the shoe being the wrong size – usually too narrow. Very often this is due to two factors: most shoe companies only make one ‘average’ or D width shoe, and many walkers have no idea what width shoe they should be wearing.
A lot of this comes from shoe recommendations made (often here on BPL) in total ignorance of the other persons foot size. Sigh. Ah well – at least I know what width shoes fit me, and I never get blisters.
cheers