Pros:
Spencer is one of the most challenging nine-hole courses I have ever played. Many tunnel shots demand an almost perfect tee shot if you want a birdie, and even the smallest mistake can leave you scrambling for par even if you had a good tee shot. There are lots of opportunities for perfectly placed tee shots and upshots, but also lots of trouble to get into.
There seems to be little lost disc potential here. The water hazards are just a swampy area that hardly comes into play, the rough isn't super thick, and the woods on the sides of several holes aren't bad, so even if you go in, it should be easy to find discs. This makes fairly quick rounds possible, which is surprising considering how difficult this course is.
The best holes are, obviously, the tunnel shots, particularly 1, 2, 6, and 9. They did leave me scratching my head sometimes wondering what the best line ought to be, but that's the point of a difficult hole. On hole 9, I don't think there's really any way to park it in 1, but I can imagine something getting in putting range. However, the mix of a few open holes here and there is a nice touch; I like hole 7, and the second half of hole 8 plays into the open but still near a treeline.
This park also has a playground, off-leash dog parks, and a walking/biking trail, none of which even come close to being in play for the Disc Golf course. Two other courses are within walking distance of this one, and the teepads and baskets are in good shape. Even after a lot of rain, this course was in pretty good shape, even in the woods.
Cons:
A lot of the fairways are narrow, meaning many drives could end up in the rough, even without unlucky tree hits. While the rough itself isn't too bad, it's very possible to have some short searches for discs quite often. On hole 5, the dogleg right par 4, you want your drive to the left to give a better look at the pin, but that would put you in the tall grass. If you count the tall grass as OB on holes 3-5, it'll be pretty oppressive and unfair.
While this course is legitimately challenging, some holes don't really make sense. I think holes 2 and 8 have gaps that are just too small, and while birdies are possible on those holes, they require just as much luck as skill. I think there might be a high right route on 2, which could be the preferred route for some because of how tight the fairway is.
There are no tee signs, but it's not too bad because the tees are always easy to find and on the only holes that you can't see the basket from the tee (5, 8, and 9), a glance at the map will show you a rough idea of where the hole is. Hole distances would help though, especially when you know where the basket is but may have a hard time judging distance.
Interstate 229 is nearby and can make the course a little noisy. Fortunately, there's no danger of putting a disc over its fence except possibly a bad shank on hole 7. Also, after hole 9, you have to walk down the fairway of 1 to get back to the parking lot (unless there's a path in the woods I didn't see).
Other Thoughts:
This course isn't just a walk in the park. If you want a walk in the park, there's a nice trail nearby close to the river. Nearly all the skills in your bag will be challenged here. I wish the fairways were mowed a little wider and some rough was cleaned up, but it wouldn't change how varied and tight many of the shots are.
Surprisingly, I didn't notice the lack of elevation too much here. I think it was because there was such great variety in the holes that there are, and with only nine holes, nothing began to get repetitive. The course would be better with some more elevation change, obviously, but it isn't a real knock on its design.