Don't the X5's also have ridiculous running costs or did I read it wrong?
Not sure if you can coax a Volvo to 40mpg but perhaps an XC90 is worth a look?
ML270 perhaps?
In Iceland I found the Nissan Qashqi to be far superior to the Suzuki Grand Vitara. - We had both as rental cars, and the Nissan never drove into anything it couldn't get out of; the Suzuki had to be rescued by a Landcruiser at on point... and I broke the traction control driving in Reykjavik.