Pros: Great steep terrain that is easily accessed without excessive hiking, cheap, uncrowded
Cons: Best runs are on the west side of the hill which is not fairing well as the world warms
When I moved to Montana 13 years ago I discovered Discovery through this site. It quickly became my second favorite ski area in Montana and sometimes my favorite. I would ski there a 2 to 5 times each year. But as the years have gone by I have been going there less. Sadly, the warming world has not been kind to Discovery. The best runs are off the Granite chair and Limelight chair. Both have a western exposure with the Granite chair being in the worst situation of having a southwest exposure. This results in warmer afternoon temperatures and excessive melt. The steep runs off the Limelight (which is my favorite lift in Montana when there is enough snow) really need a 50" base at the bottom to ski. This year its rarely been up to 3 feet.
If you happen to be in the neighborhood and Discovery has snow definitely make the effort to ski there. The 15+ true double diamond runs off the Limelight chair are the best collection of steep runs I've seen off any one lift anywhere. Just don't plan a vacation around Discovery because of its issues with getting and holding snow.