the safety and stability of a 2-up atv doesn't isn't as much about length as it is where the passengers weight is in relation to the rear axle.. On a purpose built 2-up atv, the rear axle is below and slightly behind the passengers weight center. Thats what keeps the front end down.. When carrying a passenger on a 1-up atv, the passengers weight is behind the rear axle which is what makes it easier to for the front end to come up or worst case flip over backward unexpectedly.. A rider that knows what they're doing can carry a passenger just fine on a 1-up atv, but a 2-up ride is nearly impossible to flip over backward.. Definately due to the added length, but primarily because of where the passenger sits in relation to the rear axle..
You'll love your touring when carrying a passenger, and you'll love it even more when climbing steep hills on your own. The added length makes the xp's already amazing ride even better.. And when climbing steep hills the front end stays firmly planted..