In the creative field there is no such marking like best or otherwise. It all depends on whether the music appealed to you not. If you judge a music composure by commercial success only, A.R Rahaman will be ahead because of his getting a few Oscars. But an Oscar does not matter much in Indian music , so let us not attach much to that award. Bappi Lahiri, Anu Malik and likes of them are still in business.
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It is difficult to comment. Indian Music are vast and it has its own value. World has recognised A. R Rehman. Still we should not forget those songs composed by GULJAR, ISMAIL , BAPPI DA, R.D. Barman,Himeshji ffor their creations.