As far as I know, 1C is still the ROAR rules. But I think most people/tracks don't care. 1C used to be pretty mandatory, but with the latest generations of Lipos it's not so much a worry. People are safely charging much much higher. But you can't go wrong at 1C. That's still the "recommended" rate if you want your packs to last as long as possible. But you'll get a little performance increase charging higher at the risk of longevity of life.