Pros:
The course plays through a hilly park that is mostly heavily wooded with streams and abandoned roads running throughout. Nearly all of the course is disc golf only, so there are only a couple holes where you ever have to worry about other park users. The elevation is used really well to make fun and interesting holes, especially hole 2 off the top of a bluff over a creek.
There are a couple holes that are more open, a handful of holes in scattered mature trees, and the rest in woods. This makes for nice variety throughout the round, and provides different challenges. The course never gets repetitive, with each hole seeming new and different. The design is fantastic, making the most of the foliage and elevation changes available. There is just about every kind of hole you could want here, so bring all your shots if you want to get those birdies.
Half the holes have two tees, making for some different challenges and looks at the baskets. There are signs on all the short tees, though some aren't in great shape. The tees are easy to find with red or white markers in the ground delineating the front of each tee box.
Cons:
The first time you play this course, there are some confusing spots. The holes do a nice job of not overlapping or playing too close to one another, but to make this happen there are some long walks that aren't always obvious. The worst one was from hole 8 to hole 9, where you had to walk all the way back down the fairway to get to the next tee.
The tees are mostly dirt, and can get really rutted and rough. If there has been rain recently, the tees in the low parts of the park near the creek can be pretty muddy and slick. Some of the signs are falling apart and difficult to read, so your first time out you'll have to scout some of the holes.
Other Thoughts:
Once you get past the navigation issues, this is a really fun course. There are all kinds of fun and unique holes, and the course stays fun and interesting throughout. Especially with Highland Park nearby, this course and the Joliet area are worth the drive to play.
This course is playable for beginners, with a number of shorter holes. There are, however, many opportunities to lose discs in dense underbrush, so beginners could get frustrated with that. More experienced players will have lots of birdie opportunities, but will find the course fun and interesting, and more challenging from the longer tees.