Is Choosing University of Michigan over Carnegie Mellon a reasonable decision?

@PurpleTitan Large scholarships are extremely hard to get anywhere, but UMich does have >200 large ones in LSA and CoE that are $5k-$10k for in-state and $10k-$20k for OOS. There are also ~50 full tuition to full ride. In addition, UMich would meet the need of OOS with family income below $90k. So it is possible that UMich may provide better FA than CMU to OP depending on his family financial situation. Would his HS let him proceed with OOS public college application is another story.
It seems OP is having a second thought on the ED school not because the FA is much lower than expected, he just thought he can simply back out if it is too expensive and did not even check the cost before application. It is true that one can always decline an ED offer if it is not affordable, but it is often not without consequence. He could have choose to apply other SCEA/REA school instead of applying to an ED school with unknown cost. He may have loose other opportunities as well depending on his high school policy on ED withdrawal.

@billcsho, if the OP is getting little/no fin aid from CMU (which meets full need in the ED round), I think it’s extremely unlikely that UMich gave him/her a large amount of aid as they are likely upper middle class (and OOS at UMich).

@PurpleTitan Each school determine the needs of the students with a different formula. In addition, need can be met by loan, grant, or other means. Most important, CMU does not guarantee need met. Indeed, only 30% of aid recipient have their needs fully met according to CollegeData.
https://admission.enrollment.cmu.edu/pages/financial-aid-faq

How can you tell if OP is upper middle class? Another asumption?

@billcsho, please read more carefully. CMU does guarantee to meet full need for ED applicants.

It’s hard to see someone who isn’t upper-middle-class get very little/no fin aid from CMU while applying ED.