Pros:
This course gets huge, huge props for having some of the best grass I've ever played on. I was out in Colorado for a friend's wedding and took the groom and other groomsmen to play a round of disc golf at this course. We had all kicked off our shoes by the 2nd or 3rd hole because the grass was so amazingly well kept, green, plush and beautiful. I know this may not matter to a lot of folks, but being able to wander a course barefoot and play a fun round of disc golf with good friends is one of the highest pleasures in this sport, and this course is IDEAL for that sort of afternoon.
In addition to world-class grass, the general maintenance of the course is also above average. Trees are trimmed and in great shape; the creek is pretty clear (or was when we were there), and the course is free of broken bottles and litter.
The holes aren't hugely challenging, but they do work well for a wide variety of skill levels. There is enough challenge that blue/gold players will still enjoy themselves, but players just starting out will also take some pars and aren't likely to lose discs except in one or two places along the creek (but this can be pretty easily avoided -- most wet discs are easy to retrieve).
Cons:
The course is a little challenging to navigate. The multiple pin placements aren't always well marked, and it is sometimes very confusing how to get from tee to tee. Some of the teeboxes are tucked back in trees and this makes it even harder to find your way through the course the first time. Also, with some of the pins not visible from the teeboxes, it can be a challenge to know whether to aim at A, B, or C pin position (this is a common problem, but still an annoying one, and easily fixed with good signage).
The course could also benefit from leaving some more pins in the longer placements to add variety to the course. When I was there, most of the baskets were in short, which seemed odd since it was July -- lots of daylight and beautiful weather -- when you would expect the course to be stretched out to take advantage of that time of year.
The park is also shared with lots of other activities (tennis, dirt bikes, swimming, jogging, horseshoes, etc...) and while this doesn't often come into play, you do have to be careful of other users of the park. The park stays busy, and the disc golf winds near all other areas of the park, so this is more of a problem than it is at a lot of places. We never had to wait very long for folks to move, but we were playing midday on a weekday and there were still a fair number of people around -- I could imagine it being pretty crowded on weekends (though this is purely speculation).
Other Thoughts:
Other huge props for this course -- it is very close to the New Belgium Brewery, so go by before or after and get free samples of all sorts of tasty beverages, some of which they only have at the brewery and don't distribute outside the area (some amazing Flemish sours).
If you're visiting from some other part of the country, remember that Fort Collins is about a mile above sea level, so discs will fly more overstable here than they will at lower altitudes. So plan accordingly and bring lighter or flippier discs than you are used to using and it will help your scores... and don't get frustrated when at first everything flies differently than you expect -- that always happens at altitude. Just enjoy it -- and watch how far an Ultimate lid will go at higher altitudes.... it's pretty awesome.