It's all a matter of personal preference. Some people prefer taller bars (typically street riders) and some prefer shorter bars (typically park riders), but it's all individual. Generally, your bars should be about waist-height when standing on your scooter with your knees slightly bent. Also, with your SCS, measure from the top to the ledge on the inside of the clamp to find out how much offset your SCS has. If it's 1.5", you'll need to cut your bars 1.5" shorter than if they were non-SCS. That is, the height of your bars should be the distance from the top of your headset to where you want them, minus the SCS offset, and make sure you don't have a slit in your bars.