One thing I've noticed is the shaping. Vekomas seem to transition from element to element more seamlessly (i.e. banking into turns), whereas Arrows seem to be more boxy, for lack of better terms (i.e. banking on a straight section and then going into turns). Arrow transitions tend to jerk the car more.
Notice how the track doesn't start banking on this Vekoma (Big Loop) until just as it enters the turn, and the amount banking changes throughout the turn.
On this Arrow (Viper) the track banks on a straight section. The amount of banking doesn't change much during the turn, as the track is almost at its full banking already as it enters a turn.
This is just a little thing I've noticed. Hope it helps.