Well they aint SO big,
http://www.globalsecurity.org/military/systems/ship/images/LARC-pic1.jpg
If fact these are they:
http://maps.google.com/maps?hl=en&t=k&ll=50.82632500,-1.08793300&q=United%20Kingdom&spn=0.000552,0.001207
at 97 tons the each. Well you do get one engine per wheel, with three speed Torquematic gearboxes, so you're not inconvenienced to change gear ! Mind you puncture repairs might be difficult, as the 36.00 x 41 tyres weigh just over 3000 lbs the EACH.
But Hey, What price fun ?