A buddy of mine is fond of SeaEagle's line of inflatables. He's been a little disappointed, though, with the amount of time it takes him to inflate and deflate at the ramp, even with the battery-powered automatic pump. He bought one of their kayaks last year and a four-place zodiac-lookin' thing this year. He's still trying to figure out how to make it easy to mount the electric motor to the transom.
My sit-on-top kayak takes less time to rig and launch, but my friend needs to take his son along and can't wrestle with car-topping a kayak on top of his Trooper.
Take a look at http://www.seaeagle.com/, see if there's something you like...