I have a close friend who has been doing an in-class ultimate course alongside her regular classes on campus since last semester, and she has been exhausted the whole. Some of the classes are on weekdays so it's tough to go from a full day of classes/studying to an MCAT class going until 9:30 at night.
Having witnessed this, I signed up for the self-study course through TPR. The materials available are the same as an ultimate course, except that you have all the classes pre-recorded, you go at your own pace, and it's $500ish cheaper. I've been doing it alongside my classes and so far it's worked pretty well. Since I will have to take classes full-time and work over the summer full-time, I'm giving myself 9 months to study going at about 10 hrs/week of studying (maybe slightly more over the summer). You have access to the self-study course for 270 days, which is more than enough time.