It depends on what your plans are, back yard bashing or racing. With brushless motors and lipo batteries the run time advantage of nitro has been reduced. Nitro chassis are beefy and tend to have less breakage. I would choose something that you can get parts for locally, instead of having to depend on mail order. Nitro needs glo plugs and fuel. Electric once you buy everything there aren't too many trips to the store unless something breaks. I've raced the Traxxas revo and Kyosho 1/8 buggies in the past with little problems. As for electric I have tried them all, just stick with the top brands. Check out Thunder Raceway in Nashville, they have weekly racing in onroad, oval and dirt offroad. I agree with the other posts about the Slash, I got my daughter one and I haven't had to fix anything on it yet. If I can help just let me know. I'll link to some sites and shops I use.
Matt
http://www.nashrcracer.com/
http://www.stormerhobbies.com/
http://traxxas.com/
http://www.losi.com/