Does the HR prefer an edu email from a prestigious school or a personalized domain which demonstrated some degree of technical skill?
I've never cared what domain the email address has when looking at the resume. If it is from a prestigious school, then they should have that affiliation already written on their resume. The email address itself isn't going to impress, I think.
Same goes for the personalized domain. The exception here is if they bother to look at the site attached to the domain and it is impressive. Again, in this case, it can be listed elsewhere on the resume too, if it is impressive and the applicant has the primary role in the creation of said site.
I personally see mobile email addresses / yahoo accounts / edu and gov accounts / personalized domains as the same, so I wouldn't spend too much time acquiring an email address that looks good, and just list the one that you could respond quickly with. With this said, meta data / signature should still be taken into consideration, and the non-domain part of the email address shouldn't be anything too embarrassing offensive.
The problem with your question is that anyone associated witj the school can have an email address with the domain so it doesn’t mean as much as you think. Also anyone who can pay the registration fees can set up a domain and get a personalized email address and domain so again that doesn’t mean as much as you think.
The truth is they will care more if the email/domain is unprofessional the what the actual domain is. What I would chose is the email address that will be around longer in case they keep it on file and try to contact you later.