Did a few trips with the 3800i swb and the longwheelbase diesel, the petrol did great if you rev it like a banshee. Diesel was ok but rearend acts like a sandscoop and the first item you lose in spirited driving.
Compared to x5 the overhangs is the same except paj low slung arse. Power to weight ratio much better in x5 and x power to wheels also much better. The x5 is a step above them when dunedriving.
Some video clips