AIIMS is known for some rough ragging, so as a fresher that might be tough. If you have a sibling in the college, AIIMS or MAMC can become a smoother experience.
Try to acquaint yourself with a professor beforehand, in whichever college you choose. It will help you throughout your academic years.
My friend got AIIMS Delhi in the second counseling, but by that time she had settled in MAMC and made friends. The 50% DU quota for PG is another way.
AIIMS is AIIMS, so there's no comparison.