I wrote a piece comparing MHCI and MDes program at CMU. I'm a junior student currently in the BHCI program, and I've been doing a lot of research on this while deciding which is the right program for me - a lot of the insights were not available on the Internet. Hopefully, it's helpful to some people!
https://medium.com/@songyh1996/mdes-vs-mhci-carnegie-mellon-university-bfb185c71e63