It Ain’t What You Do, It’s the Way That You Do It
There are many different “vehicles” that can be used for meditation, including the breath, a mantra, the open sky, or the simple sense of “I,” and any of them is fine as long as you feel comfortable behind the wheel. Much more important is how you “drive” the vehicle. Use a light touch, with a minimum of doing. Don’t try to concentrate on the mantra (or whatever), don’t try to make it hold still, just lightly rest your attention on it and let it go wherever it goes. It’s the self-driving Google car - you’re just along for the ride.