There is a fundamental way to use mantra meditations and if done correctly, it can be a great device to go higher in meditation. Our minds are cluttered and is full of thoughts, and so many of them. There is no magic razor to cut these thoughts. Mantra can be a great device to bring order into these thoughts. A meditator should mantra as one mindedness tool and just focus on repeating the mantra. Every now and then, you will wander and move with other thoughts, and that is the time to use your discretion and bring your focus back to the mantra. With practice, you will be able to become one minded with the mantra and hence the other thoughts will slow down. Thus using mantra in a right way requires to use it as concentration tool. After reciting of mantra for a certain amount of time, the next phase of meditation should be purely witnessing without reciting the mantra.

With the above fundamental principle, one can use it well to reach state with low thoughts and thus go higher in meditations. Further, there are Mahamantras, which certainly have good sound vibrations that further add beneficial effects to the meditation.

Even chanting, “Coca Cola, Coca Cola, Coca Cola…” can be just as good if you keep a clear mind. But, if you don’t keep a clear mind, even Buddha cannot help you. The most important thing is, only do it. When you only do something one hundred percent, then there is no subject, no object. There’s no inside or outside. Inside and outside are already one. That means you and the whole universe are one and never separate.
– Zen Master Seung Sahn

Yes, I have also tried with Coca cola and it works equally well provided, you are able to reach that one mindedness or as Zen Master Seung Sahn calls it one hundred percent.