It all depends how much you have to spend.
If you are new I would recommend the Losi 8ight 2.0 RTR. For around $650. This is the best value on the market by miles and if you are looking for a competitive racer you wont get a better deal.. Comes with an awesome radio, starter box and almost everything you need to get racing.
If you have more I would recommend a Hot Bodies D8 kit with good but average components. Probably around $1000+-
If you are looking for an awesome setup. My recommendation would be a Mugen MBX6. Losi 8ight 2.0 roller, Xray 808 09 spec, OFNA Jammin X2, Hot Bodies D8, RC8B, etc (Random Order). Good motor like a V-spec, Speed, Niji JX, etc. Good Pipe, Good Radio, Good Servo's and good everything else. Your looking at $1300+-.
These are all in new prices and might be really steep for you. You can probably find a used 8ight 1.0, Jammin X1, RC8, etc for really cheap. If you have more question it would help if you had a price range so we can try and build you the best vehicle for the price. But if you have the money and are just getting into racing, go with the Losi 8ight 2.0 RTR without a doubt.
If you are bashing I might recommend something else. Bashing with a starter box can be a pain because its another big thing you have to carry around.