I'm surprised they have you apply it with a bottle like that. It seems like a spay bottle would be a better tool to evenly distribute the oil, while simultaneously help minimize the chance of using too much oil. Maybe the oil is too thick for any kind of spray bottle.
Mostly looks and their install design. I think the S&B looks cleaner and nicer, but the K&N setup is fine. I don't think there would be any rear world performance differences between the two, but I haven't personally tested it.
