Pros:
SeaTac DGC is a 27-holer that sits in a large park of the same name, in the urban sprawl between Seattle and Tacoma. The disc golf course, park, nearby airport, and 'burb all share this smashed-together "SeaTac" name. Based on the course description here and what appeared to be old building foundations on/near a few fairways, I believe that this park used to be a neighborhood.
The golf here is quite good for an urban park course. There are a great mix of holes, from "mostly open with a couple obstacles" to fairly tight technical throws. Nothing is thread-the-needle tight, but shot shaping is required on most holes. There are ample left turns, right turns, and straight shots. Many baskets are guarded by trees and/or bushes. The distances are enough to challenge most of us mortal disc golfers. The shortest hole here is the finishing hole 27, which is only 229' but plays to a basket raised up on a large mound. The average hole distance is over 350', and there are several respectable par 4s - the longest being hole 21's 547'.
I thought two of the more memorable holes here were back-to-back - #15 and #16. Hole 15 is only 250' but requires a controlled tee shot through a small gap in some bushes, to a basket framed by tall trees. Right after that, hole 16 plays 320' along an S-shaped fairway with a grove of trees in the middle of the first bend. These were both very fun and aesthetically pleasing holes. Overall, despite being in an urban area this is a visually appealing course.
The baskets are DGA models in good shape. There are also a couple of practice baskets next to the parking lot.
The rough is thick enough to punish poor throws, but didn't look likely to hide discs. Beginners and families won't score well here, but could still enjoy the course and probably not lose any discs.
The tee pads are concrete and in good shape. The tee signs are large and show all of the needed info (hole number, distance, par, and map of hole). On some holes (not all), different pin positions are shown on the tee signs and the current pin position was labeled with a tack. I believe there were a couple of holes that had multiple baskets installed, but on most holes you can only play one layout. I'm not sure how often the pin positions may be swapped out. The tee signs also point towards the next hole.
Many tee areas have benches, and some have trash cans. A large kiosk at the parking lot shows a nice map of the course, detailed hole info, disc golf rules, etc. A restroom is apparently available, although it is at the far end of the large parking lot and I did not try to use it.
Playing all 27 holes takes some time even for a solo player, but if you use the map there are some opportunities to cut off sections and play fewer holes if you are short on time. For example you could easily play holes 1-5, then skip to 24-27 for a 9-hole round.
Cons:
A couple of holes play near walking paths, and a couple of holes are pretty close together. Nothing egregious.
The course is pretty much flat. The park isn't pancake flat, but on most holes the terrain is not hilly enough to affect play. There are also no water hazards.
Even with the previous tee signs pointing towards the next hole, I could have used a few more navigational aids. A few baskets had arrows hanging in the bottom, but this wasn't consistent. I had to pull out the map a couple of times, in particular on a long walk between holes 5 and 6.
Very minor gripe, but there is quite a stretch of long holes about 2/3 of the way through the course. With only one exception, holes 17-24 are each longer than 400' - and all six holes designated as par 4 fall within this section of the course. Although this is kind of balanced out with shorter holes before and after this section, I would ideally prefer to see the longest holes sprinkled throughout the course instead of being all grouped together.
Other Thoughts:
Although the disc golf here is good, what I will remember most about this course is constantly being able to look up and see huge commercial airplanes at close range coming in for a landing. The park appears to be more or less directly in line with the landing runway of the Seattle-Tacoma International Airport and only a mile or two away from it, so during my round in the middle of the day on a Friday the sights and sounds of incoming airplanes were more or less a constant. Normally I count road noise as a minor Con for a course, but in this case I felt the air traffic was kind of cool and unique. It was not something that I had experienced on a course before. On one hole I was able to photograph an incoming Lufthansa airplane just as it crossed over the fairway. It was close enough that the company logo is clearly readable in the photo, and I could easily count the number of windows on the plane.
On a personal note, this was my first course played in the state of Washington - and the Pacific Northwest in general.
Overall SeaTac DGC is not a destination, but definitely a worthy stop for DG'ers visiting the greater Seattle area. It offers solid golf that will challenge most players, at a convenient location close to the airport. It fit the bill for me as a way to spend a couple of hours before picking up some friends from the airport for a long weekend in Olympic National Park. I think that this course is accurately rated here, and pretty much maxed out on the land available. Kudos to the locals on a job well done!