Pros:
The summit course is in and boy is it spectacular. You have two decisions on how to get up to the top with either paying the $20 for the chairlift or going hardcore and hiking all the way up for free. Once you get to the top take pictures! Mt. Rainier looks HUGE because you are so close and Mt. Adams in the distance also unbelievable in it's size and beauty. Many times during the round you will want to stop to take in the scenery and take a rest as well. Once you play the first nine you have the option of taking the lifts back down to the lodge or playing the back nine of the bottom course to get to the bottom with hole ten on this course and the bottom course being the same basket but from this course you throw downhill instead of uphill at it.
This time of year there is still some snow up there and this keeps you cool on hot, sunny days more than 5000 feet above sea level. Since the course plays all down the mountain you get all of the big fun downhill throws without the pain of trying to play and hike uphill with your disc golf bag on. This course takes extra time to play to give yourself enough time to take it slowly and have fun.
Cons:
The cons are fairly obvious, if you don't like elevation both for a disc golf course or for walking on then this course is not for you. You can catch the wind wrong or slightly screw up your throw and watch a disc sail into the abyss never to return. Since you are throwing so far downhill it is tough to judge where your disc landed and walking up and down the mountain to look for it is tiring to say the least. Most of the tee pads are dug out of the side of the mountain and others aren't manicured at all and have you throwing off the side of a hill with no footing and no chance for a run up. The baskets are all temporary ones with single chains and spit out many putts.
Other Thoughts:
I recommend bring your "B" and "C" stock discs to avoid losing your favorite ones. I would recommend being extras in case you lose some even though it's more weight to pack around. Bring food, water, sunscreen and sunglasses while you're up there as well. There is talk of another nine holes going in to connect with this course somewhere but the details aren't clear yet. Stop by the Snorting Elk Lodge for food and drinks.
Update:
The gondola is now up and tickets cost $20 person to get to the top.