Two women of the same age are restrained. They're both hot, have great laughs, and have very attractive and super ticklish feet. But you can only tickle one of them.
Would you tickle the women with small feet or big feet?
It would probably never be boiled down to just that variable for me, but I get the hypothetical with everything else being equal, I'd prefer the smaller feet. Again, just a preference–I love both.