From my experience I found two universal rules:
1-Attending any lecture is beneficial (regardless of the subject and no matter who the professor is) at least you get to memorize the main points of the discussed material, if not more...
2-Every single lecture (regardless of the subject and no matter who the professor is) has its share of killing boredom
The question is: is it beneficial enough to bear that boredom? Is it really worth it to miss what you may do in this one hour (or in my case 2 hours)?
My personal answer is: very few lecs are worth it and this is the case specially in the basic medical sciences lectures (Anatomy, Histo, Patho...)..
I mean come on, we have a social life, we have lots of other things we can do in this time..
So my future resolution is to attend one lecture (or two at most) for each new professor to asses and weigh each side of the equation