For bashing, the HPI because most hobby shops carry parts for it. The same for club racing. For more serious racing, neither. That is where you would go with the R40, if you like HPI, or Serpent, Kyosho, or Mugen if the R40 is not your preference. Kyosho and Mugen parts are easier to come by than Serpent's in many areas and would probably be better choices but all three touring cars by them are very comparable.
It's not what you know; it's what you can prove.
The only thing that is for sure is that nothing is for sure!!!
The needs of the many outweigh the needs of the few, or the one.
There are 2 things in life that are infinite: the universe and stupidity.