Better is up to you. I have both the M9 and the M6 and have read the claims that they have the same driver. Honestly I rather doubt this claim as they sound quite different. Of course, it could always be just the fact they have different housings that cause the difference. Regardless they do sound different. The claims that the M6 is better is more or less true depending on how you define better. The M6 is superior to the M9 in just about every way except sound stage and airiness. But like I said upfront, better is up to you. Some people prefer the M9. Unlike the M6 it does not have to be worn over the ear (yes, the m6 must be worn over the ear). It also packs more bass than the M6--not better bass, just more. It also has the benefit of metal housings over plastic ones. Personally, I like both for their own reasons. If am I am in a "crank the subwoofer up, feel the bass mood" I grab the M9. If I am in a more "I want to hear sparkly highs mood" then I grab the M6. My advise on which one to buy would basically be this: first do you mind over the ear? If yes, buy the M9. If no buy the M6. And Second, do you prefer to feel the bass or hear the bass? If the former buy the M9. If the latter buy the M6. (Not saying the M6 is week in bass mind you, just not as excessive.)