Sony won't output surround sound data to headphones unless you buy one of their headsets, or use a headphone/receiver that supports an optical connection with an older PS4 or a PS4 Pro (as the slim cut the optical port).
So, if you're looking at these two models for their surround support on PS4, you'll have to look elsewhere. On PC, the Alpha S has true surround processing, where it'll take surround data from games and mix it with binaural cues so you can hear it over headphones. The MH752's sound card doesn't support surround data even on PC, instead upmixing stereo. In both cases you could also use Windows Sonic or Dolby Atmos instead of the card's built-in processing...again only on a PC.
In terms of raw audio quality of the headsets I'd say they're both very similar. The Alpha S has more bass, which you can further enhance with its bass adjustment sliders.