Brand wise, both are a bad choice. Ash is stunningly beautiful, but most people actually don't like her (reason could be their own complex, her plastic behaviour, etc). How can a person be a brand ambassador of a product when the person is actually not very likable.
Frida is again a bad choice. She really has no pan-India appeal and her looks are pretty ordinary and girl next door.
I don't like Sonam a lot....but I suppose she could be their best choice if L'oreal wants to expand in India.
Ash is now too old for the show and Freida looks like a plain jane, infact she is not beautiful at all and is a bit ugly, at least Ash has better looks and i dnt think any actress must be compared to frieda who is quite ugly.