Take the easy A course. You're a nontrad premed student, you are not there to be inspired to go for a Physics PhD nor should you trade your 4 months of amazing physics with XX% less chance of becoming a doctor due to potentially lower GPAs. Most of your study from now on (postbac, med school) will be self-study anyway.
Go above and beyond so that you won't become complacent while taking that class. If that easy A class require a 90% for an A, strive for 95%. If that class doesn't require weekly homework, assign yourself all the end of chapter problem sets. If the class doesn't require reading from the textbook, read anyway instead of relying solely on PowerPoint slides. That would help you with MCAT content review. Also, from my experience, you need to be good at Math to do well in Physics (or just about any science courses, especially Chem), so do yourself a favor and review math materials really really well.
Still, as a former tutor and TA, I do agree that a good teacher can inspire a student to do significantly better on a subject.