Totally understand the comments about being lazy, but when you're pressed for time, and you're blowing up 12-16m kites everyday during a short lunch break, the electric pumps are AWESOME! Your kite is actually fully inflated before you finish getting your lines out.
The Ryobi's only get your kite partially pumped (maybe 3psi).. While that is a good amount of volume, they don't do high pressure, like the WindChaser Sports pumps do. It definitely removes many manual pumps from the whole process though.
In any event, I just bought one of these electric pumps from http://www.windchasersports.com/#!pump/c1yc2
The sand filters are key too....when you got sand blowing around on the beach....