looking for a few answers on brushless systems from the resident oracles here, any help greatly appreciated.

I'm looking to move into 1/10 offroad electric racing and was wondering why brushless motor's haven't really taken off at a competitive level yet?

The on paper specs suggest brushless's (such as velocity 4.5 or Nosram 3 or 4 star etc.) should be competitive against mod motor's, why do none of the top line guys use them for competition?

Anyone have any experience of a brushless compared to a brushed mod motor?

Thanks,
Brad