that demo did indeed look like some fun, although extremely unrealistic in respect to the capabilities of the ARFF trucks.
those truck would have most definately rolled on all of those turns due to the high C.O.G as previously stated. A Stryker at MEL
jacknifed at 10kms a hour going full lock because of the forward motion of water and AFFF under brakes (commonly known as inertia).
Other worthy point to notice is that the monitors going hammer and tong up the top will only last for around 45 seconds before water and AFFF is exhausted.
Contracts and standard regualtions at different airports vary but plans are devised for routing to just about any given point on an airfield and a 42 tonne truck will avoid leaving the tarmac unless absoloutely no other way is viable.
Last point to notice is the distance the trucks were positioned in relation to the aircraft, far to close the monitors for the most part are capable of covering a 747 nose to tail hence the need to be so close is not apparent, that said this simulator isnt reality for training fire crews merely a bit of fun and fun it does look.