Congrats on the dual admits. I'm considering applying to both part-time programs as well
From what I have gathered, Booth's part-time program has a few advantages:
-Students do not need to remain employed (if you lose your job you can take a full-time courseload)
-Students can bid for classes at the Harper Center, although it will be difficult to get them.
-Students can recruit along with full-time Booth students (same events).
Negative for Kellogg
-Students receiving tuition assistance from their employers cannot recruit on-campus.
-Students must remain employed (I believe this is true, but I might be mistaken)
Both schools are great, but I'd say it comes down to what you want out of the experience. Go to the school that has the best course offerings, culture, facilities, etc. I would be receiving employer sponsorship, so I would probably choose Booth just incase I lost my job or decided to recruit for a new one.
I haven't visited an info session for either of these part-time programs. I have only visited Booth's Harper Center.