Varied Terrain, Expert Runs, No Lift Lines
No good apres-ski, misleading statistical advertising.
Our ski club just had 40 people of varying skill levels go to Big Sky and everybody left happy. This resort suites all kinds of people except maybe spring-breakers who want to party more than ski due to the almost non-existant nightlife. While this quality makes it very family-friendly it would be nice if there was a hopping bar around even if it was a little off-site. I didn't really mind this though, as I was so tired after the days of great skiing to go out anyway. Due to the company that owned the lodge on top of Andesite mountain folding, eating during the day can be a challenge as well, as Whiskey Jacks at the base and the lodge at the bottom of Iron Horse lift are the only good options for lunch and even with Big Sky's thin crowds can get a little busy on the weekends. If you're looking for a place to stay try the Lodge at BS. It's not ski in/out, but is a short walk away and has a free shuttle.
There is one thing people need to understand about Big Sky before they go there: the size statistics are a little misleading. The claimed vertical rise is about 33% made up of the Lone Peak tram, a lift many skier will not be able to descend from due to the extreme terrain. The lift attendant makes a point of telling you "there is NO EASY WAY DOWN!" The next highest lift is the aptly-named Challenger lift, which is equally daunting. The lowest 800' of vertical is also only served by one lift most will never ski. So basically, don't go there expecting nothing but long runs, especially if you are a groomer skier. Big Sky does not groom Blacks, but many of their Blues would be Black elsewhere. The most vertical you'll get one Blue run is about 1700', but neighboring Moonlight Basin has some long Blues. Also, while BS advertises "The Biggest Skiing in America" based on acreage, this is only true if you get the combination pass with Moonlight Basin. Big Sky by itself is "only" about as big as Telluride or Steamboat. Should you get the combi-pass? It is more expensive, but yes. If I had to do it over again what I would do is ski a few days at Big Sky only, then get the combi-pass with Moonlight for the last few days so that you can flit back and forth on a whim, especially on windy days were you are looking for protected coves of powder.
That being said, BS is one of the best resorts I've ever been to and I'm going back at the earliest opportunity. I became a much better skier there BECAUSE there is no easy way down the Lone Peak tram. I told myself I was not leaving without having skied that gorgeous mountain, and after a few long leg-burners and a little time watching the pros do it I got pretty good myself. Liberty Bowl is the easiER way down, and it's still 50 degrees, but very wide. Marx and Lenin are more fun, and Lenin narrow and very steep at spots. If Lone Peak gets too sun-baked or wind-blown but you still want to ski some steep-and-deep head over to the Challenger lift. Even the ramp getting off of Challenger is a double-diamond, so be prepared.
I think Big Sky could compete with Jackson Hole for extreme terrain. The A-Z chutes are an easy hike from the top of Challenger, and some of the stuff off of Lone Peak is insane. Big Coulier requires avy gear and a signed waiver to ski. The Gullies do not, and feed into Big Sky's "Bowl", parts of which also get pretty steep if you traverse over far enough.
If tree runs are your thing then you've got options everywhere. The Dakota lift is trees-only, but it points Due South, so there are days it's not good. Stump Farm and Park Saddle Glade off of the Swift Current Lift (the "main" lift) are winners, but I think the best tree runs are in the triangle between the Thunder Wolf lift and Ramcharger. Thunder wolf also serves what the resort claims is the longest mogul run in the US (snake pit) and the longest Blue Cruiser (Elk Park Ridge). I think whoever concocted these claims would also sell you a bridge. While EPR is a great run, I know I've skied longer, and Nightmare at Telluride also makes the longest-mogul claim.
If you like cruisers you'll love Big Sky as well, despite it having less groomed vertical compared to Vail or Telluride. Southern Comfort lift has a lot of greens while Thunderwolf, Ramcharger, and the Swifty have some wide-open bombers. Silver Knife, Tippy's Tumble, Bighorn, Ambush, and Calamity Jane are all top-notch. Be advised though, they may not groom all the blues every night, so take a peek at the grooming report in the AM. Grooming is the one area where neighboring Moonlight Basin is ahead of Big Sky.
As for Moonlight, I plan to review it as well but basically it's just as good only smaller. The two areas have one "common" lift (Iron Horse) and because of this common lift it's harder than it looks to accidentally get into the wrong resort. Big Sky offers free mountain tours, and you should take one the first day just to get the layout.
I loved Big Sky/Moonlight and cannot wait to go back. The only flaws are the lack of a nightlife and not having any true top-to-bottom groomed runs, but the enormous width of Big Sky/Moonlight more than makes up for less vertical. It's great for anybody.