I've seen guys in 4wd SC with the best of everything get smoked by a guy with a $25 tacon motor and HW esc, turnigy battery, bald tires, trashed body with a hyper10sc. He Smoked all the new breed trucks. You see if your a good driver you can get by with a modest setup and nothing special. Look for a used rtr with good stuff in it and save bunch, learn to help yourself there are plenty of budget items on the market.
I agree the prices for top gear is high, maybe a slash 4x4rtr would be the best bang for your buck right now and still can be competitive in the right hands.
good luck buddy!