Never had a Presta that didn't leak!
Never had a Shrader that I couldn't use one of those portable
battery air units to work just great!
Never had a Presta that I could EVER get the required amount of air
in without the battery pack going DEAD long before that happened!
ALWAYS had to go to the gas station to get air for ANY tire with a
Presta valve in it!
ps: I don't like Presta valves!!!