Prof Bradley is such an amazing professor. Go to his office hours! He actually makes it very clear what he thinks is important and might show up on the midterm if you attend OHs. If you're stuck on a question on the midterm/final or don't understand the question, ask him! He's very helpful. Like everybody else mentioned, he makes lectures very interesting and enjoyable.
Although I have not yet finished this course, I can already say that Dr. Bradley truly cares about student learning. He is indeed a personable person and teaches microbiology with enthusiasm and humor. One upside to his lecture style is that you will never fall asleep; Dr. Bradley connects with his students, partly because he has that type of personality himself. More importantly, he is akin to the needs of students and so he tries to provide as much help as possible during office hours and in class. He literally tells his students what he expects them to know on the exam, contrary to what some others might have said below me. Dr. Bradley's questions, however, are much more difficult than Dr. Gunsalus' questions. Bradley requires you to understand mechanisms, experiments, and big concepts. He asks a lot of hypothetical "situation" questions so that you can apply your knowledge. If you attend his office hours, he is always willing to help in any way. I have found that he is increasingly willing to give you hints about what he likes if you ask him. But... as I already said, his questions are not as easy as Gunsalus'. Anyhow, this is an excellent course, independent of the instructors. I am impressed with the topics they chose to teach because these topics covered a wide span of topics, which caused me to stay interested.