I have a bit more insight in this area because I got into NAU Flagstaff and learned a ton about people that got into both or why the choose CU Denver over NAU.
Similarities:
*Amazing faculty—NAU Flagstaff has most of the core faculty and CU Denver is just one program with a large roster of core faculty
*Higher cost of living compared to some
*Lots of outdoors things to do
*High first time NPTE pass rates
*Both programs prepare and produce amazing generalists
Differences
*NAU PT classes are in an older building
*CU's building is more modernized
*NAU has slightly higher first time pass rates, but at that's also dependent on students.
*NAU is more neurological in focus
*CU has a few more experts in different specialized fields
*NAU is slightly shorter in duration (2.5 years) and where the difference in cost comes in
Overall, choose the program you will be receive the best education for yourself/be happiest at
Also, consider where you want to spend the next ~three years of your life and not let it all come down to money. Especially if you have a supportive partner or are single in a good spot financially.
It would be cool to be classmates, but best of luck either way!