I use brain.fm, but I would not say "they boast a lot of actual research". Their single "performance pilot" paper is mostly marketing, with a single trial on 1

I use brain.fm, but I would not say "they boast a lot of actual research". Their single "performance pilot" paper is mostly marketing, with a single trial on 12 people with no details on statistical significance. The effect could very well be no different from white noise.