Pros: A career in research is often times exciting and always changing. As a researcher, you get to plan your day and your schedule can be flexible. Microbiology, in particular, is an expansive field. You can focus on infectious diseases, agricultural, environmental, industrial, health promotion like probiotics and vaccines, and many more.
Cons: Experimental failures are the norm not the exception. Depending on the experiment, hours can be long and some weekend work is common, particularly early in your career. There are too many PhDs in the life sciences. Finding a job after your postdoctoral training is challenging. Only get your PhD if you are sure it is required for your career goals.