I'm currently at NAU and love it. I don't know how to compare it to the others that you mentioned, but per the US News & World Report rankings, Regis is #27, NAU #34 and Pacific University #75 (not University of th Pacific). Methodology is questionable, but it's one way to compare.
What I know about NAU:
Flagstaff campus
- faculty and staff is top-notch, very up-to-date, enlightened and approachable, and completely dedicated to helping every student in the program succeed
- didactic portion is built on foundations of PT, with a focus on producing good clinicians who have a wide base of knowledge who can take their careers in many different directions
- building and facilities ~ 25 years old; not state of the art but sufficient for what we need
- Flagstaff is pretty awesome
- tuition at NAU is on the lower-end of the PT school spectrum and you can easily get AZ residency for your 2nd & 3rd year (to take ~ 20k off total cost)
There is also a Phoenix campus, which I don't know much about aside from the fact that they just started this past year in a spanking new building with all of the modern amenities that you may be looking for.
As I said, I couldn't be happier with the program at NAU. They've had the program for over 30 years and know what they're doing. The professors & classmates are great and there is a cool sense of community in the program. Flagstaff is beautiful and the cost of the program is relatively low. I can't imagine being happier and feeling in better hands anywhere else.
Congrats on having three solid choices. You can't go wrong with any of them. Good luck!