That's interesting Steve Thankyou. 
Iirc there is only a small boot hatch to the back seats, as opposed to the omegas larger opening. So I guess a larger cylinder tank wouldn't be a problem in that large boot. Apart from loosing the smaller hatch?
There is a 'ski' hatch, no where as large as the Omega's. I use it for a ski (a slalom water ski in my case - just to keep the car industry marketers happy that someone actually uses a ski hatch for skiis) and timber too. Encoachin gon the bott was a no no for me. However with the so so fuel consumption the toroidal tank gives limited range.
Yes to to toomany rear tyres, all that torque sems to cause the rears to be worn after about 8500 miles! I keep trying to drive gently but then thnk 'what the hell'.
Steve
[PS Can I get an email notification if a reply is made to this?]