Pros:
The disc golf course at Comissioner Park is a pretty average NW Illinois course that plays over open grassy areas and has just a tiny bit of elevation. The park itself seems fairly well kept up and is clean with short mown grass when I visited. The tee signs are also pretty nice (see pictures in the media section) and give you all of the information you need to know (hole distance!). Perhaps the only interesting feature of the course for the experienced player is the "Impaler" hole where a large electric line tower is in play.
Cons:
Take a quick look at the 'Media' section here and you'll probably immediately know if this course is what you are looking for! The place is wide open with only very, very small pine trees and young plantings which really don't offer any challenge, yet anyway. On any hole with trees, you'll be able to easily launch up and over with big hyzers or tomahawk shots. As other reviewers have mentioned, the con that is not apparent from the pictures are the tees which are nearly unusable for any sort of runup.
Other Thoughts:
The beginner and family crowd will probably enjoy playing in a park which has obstacles that aren't very menacing (small pines and the "impaler") and course-baggers will likely also enjoy the impaler just because it is a bit of a unique touch. Those looking for quality or a challenge really will not be satisfied with this 'typical' NW Illinois course.