I have my MBA from the University of Phoenix. It was a 12 class 18 month program (straight through with no breaks). It was the most cost effective MBA program I could find but I did it full time while working full time. So I basically didn't have a life for 18 months straight so I wouldn't recommend doing that. I just wanted to get it over with ASAP to start my career as a Loan Originator (Which wasn't needed, it is just a credibility factor due to my age and limited work experience). Part time would be the better option for sure.
But I'm a big advocate in higher education. I can say one thing that my MBA allowed for me to become a very good writer and much better at communication. When I'm constantly presenting in front of realtors or a first time home buyer seminar, my MBA experience really shows.
In addition to my mortgage job I also own a franchise business which also was a big proponent to getting my MBA.
Hope this helps.