I've used both 6'' and 7'' now, and for me 7'' is the winner, swap is very easy, the tires bigger with puncture resistance & durability.
These are defiantly durable tires and bigger than basic setup, i like the swap.
Love my new 7'', just on my onsra had to take of the motor pulley caps, to avoid option of tire touching motor pulley cap. the board now runs even faster.
Love this tire, was looking for replacement for the standard 6 inch and faster roll, so these 7 inch just great, think I'll stay with them for a while, the swap is easy, but the ride is much more smooth.