Hi Austin. Interesting question. Hopefully one of our Contributors have an insight into this. While I can't provide you with the answer you're looking for on this point, I do know that the EEG devices you mention above are very popular, and gaining traction, in the advertising and marketing industries. I have a number of friends that work in these areas, and advertising agencies in particular appear to be buying the EMOTIV devices by the dozen! I'm not certain they're so interested in the mechanisms of learning though ...

There’s solid evidence that portable EEG systems—even inexpensive systems designed for the videogame market—are comparable to medical-grade systems. Our group at Macquarie University have demonstrated this for visual paradigms, examining the neural signature for face recognition (de Lissa et al., 2015), as well as auditory paradigms, examining conscious and subconscious attention (Badcock et al., 2013). We have even tested auditory paradigms with children (6 to 12 years of age) and the portable EEG system works well (Badcock et al., 2015). As to whether these systems offer insight into student learning, there is potential but we’re not there yet. The portability and cost of the systems allows for research in classrooms with large numbers of children in ways we wouldn’t have dreamed of 10 years ago. However, whilst neural signatures of learning or readiness to learn are exciting prospects, the research is still in its infancy.

References
Badcock, N. A., Mousikou, P., Mahajan, Y., de Lissa, P., Thie, J., & McArthur, G. M. (2013). Validation of the Emotiv EPOC ® EEG gaming system for measuring research quality auditory ERPs. PeerJ, 1, e38. https://doi.org/10.7717/peerj.38

Badcock, N. A., Preece, K. A., de Wit, B., Glenn, K., Fieder, N., Thie, J., & McArthur, G. (2015). Validation of the Emotiv EPOC EEG system for research quality auditory event-related potentials in children. PeerJ, 3, e907. https://doi.org/10.7717/peerj.907

de Lissa, P., Sörensen, S., Badcock, N., Thie, J., & McArthur, G. M. (2015). Measuring the face-sensitive N170 with a gaming EEG system: A validation study. Journal of Neuroscience Methods, 253, 47–54. https://doi.org/10.1016/j.jneumeth.2015.05.025