I prefer a geared bike just in case I break down, gears make pedaling a motor bike that is not running much easier. My buddy prefers a single speed coaster brake bike. When we've been out riding and his bike stops running, for whatever reason, he rides my bike to his house and gets his truck while I wait with his bike.
It really just depends on personal preference. I day-dream about getting a shift kit one day so a geared bike fits in my day-dreams.