well you could start with a roco 5t MAN ,they are perfect for a first truck,they look good,come with real rubber treaded tyres and have plenty of room for all the electronics,i would recomend you start with one of these.
make it 2wd and they are very releable,mine has done about 60 hours runtime with no problems whatsoever
the last truck i made was a 1 tonne landrover,about thalf the size of the man,whilst its nice to look at and drive,it does suffer on the downhill sections as its got a very short wheelbase,out of them all i just love the roco MAN 5t,it just oozes offroad
dave