Another general benefit of using brainwave entrainment in general is that it increases and promotes whole-brain functioning, meaning that the two hemispheres of the brain grow more connections and exchange information more easily. This can help more starkly rational people become more intuitive, and more airy-fairy people become more focused and logical.
Different people have different requirements when it comes to frequency changes in the music and it's quite impossible for us to anticipate them all. We would need to produce so many different variants of all our music productions that it would be impractical to manage and confusing for our customers. For example, if we were to start raising the frequency from theta up to alpha between the 50-60 minute mark of a piece of music, this would be useless to someone who used the music for a guided meditation that was only 45 minutes long. In the early stages of the development of our brainwave entrainment music we had so many different requests from different people that we could only opt for the simplest solution, which is to use a consistent frequency throughout. It might not be the absolute "perfect ideal", but this is still a very effective technique and the feedback we've received on our brainwave entrainment music has always been exceptionally positive.
Additionally, most of the studies have been conducted with extremely small samples and the touted benefits are vague. When studying the effects, it would be beneficial to hook each participant up to an EEG, note initial brainwave activity, then post-entrainment, note any changes. Although certain conditions share similarities in brainwave activity, this is clearly not always the case.
Both brainwave entrainment and neurofeedback deal with brainwaves, but the similarity stops there. Entrainment pushes your whole brain into a pre-determined state, while neurofeedback teaches you how to move specific parts of your brain on your own. It is the differeence between forcing the brain into a given position, and skills building so you can move it there yourself.