Hi Jbon,
Firstly a very warm welcome to the Scale Models forum. I hope that yiou enjoy your time here, benefit from our extensive resources and contribute your own experiences.
As for your choice of car I am certainly not the expert here but I am sure that the guys in the know will offer thier advice later.
As with most competition modelling though it all depends on how much you want to spend. To start with I would have a look at off the shelf stuff from Tamiya or Kyosho, both of which manufacture models specifically for off-road use at reasonable prices. As you are competing in a local park I assume that you are looking at electric powered models so using a standard kit from either of these model manufacturers can then be upgraded at a later date with higher performance motors and battery packs.
Have a look at these links to give you something to think about
:
http://tamiya.com/english/e-home.htm http://www.kyosho.co.jp/web/products...e/index-e.html