One thing is for sure. Kareena is Kareena. In a recent interview with TOI, Kareena said that Priyanka's special appearance in Ra.One and Katrina's in Bodyguard does not really matter as it is not relevant to the story.
Catch the whole interview here
Here are some interesting excerps:

Credits:CNNGO
If I were to stop an average person on the street in most countries outside India and ask whether he or she has heard of Amitabh Bachchan or Shah Rukh Khan, the answer is likely to be no.
Indians, fueled by their shrill media, will no doubt take umbrage at this, but that’s a hard fact of life.
Our stars are not as important abroad as we think, barring a few pockets where Indian cinema is popular.
India’s most popular acting export today is 26-year-old Freida Pinto, like it or not.
WHAT HOLLYWOOD CRITICS SAY:

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