[Gustav]

It depends whether traction is at a premium.You will get more forward traction with a rear overhang,but there have been successful buggies with the motor in front.The people that make the x-5 have a new one called the x-2,for more on power steering.Batfish converted a jato,i think he did have traction problems i'm not sure.If you think about it though,nitro stadium trucks work with motor in front and reciever pack overhanging the rear.Probably less of a problem for a heavier vehicle but the Havoc is said to have good traction.You won't get the pack down the centre line though for lower yaw moment(quicker turn in) but doesn't really matter for a basher.
Depends what surface/tyres too whether traction is a problem.
Stampy,I thought you'd tried the RS4MT in 2wd and it was OK,give it a go,basically the same layout as a converted nitro stadium would be.