My dad owns a BA XR8 and I have a BF XR6T. Having driven both I love the ability of the 8 to 'hang' the rear out (in my driveway of course) with ease, they have the torque that's for sure. You can still do the same in the 'T' by keeping it on boost. The XR6 feels a little more nimble and feels like a smaller car to drive. I think the main diff is the fuel economy. With my dad chugging around in his 8, cant manage any better than 14L/100km. However in my 6T, im consistantly getting 11l/100km and that's giving it the boot here and there.