The trend is toward laminated printed graphics (see: dirtbike style) but it will always be cheaper to do layered standard vinyl where sections are replaceable instead of re-doing the whole thing. I go by the 20' rule -- I don't care if the kart looks good at 2' away, I care what it looks like 20' away. Most of the cool printed graphics aren't even seen at speed, farther away than 5'. Unless your kart is meant to be a social media photo queen, I'd use layered standard Oracal 651... Also, fluoresecents can't be printed, so you'll have the bonus of brighter options with standard vinyl. All IMO, of course.