Huge, usually tons of snow
Expensive, can be crowded
I have been going to Mammoth every year for at least the last 15 years. For the most part, this has been a “Southern California” mountain. Recently, in the last few years, there was a push to make it more accessible for others around the country. Unfortunately, this led to a massive hike in ticket and lodging prices. There are still some great deals to be had, but I'm not going to let you know what they are.
Anyway, the mountain is fun. Nice terrain, good vertical, with mostly wide, long cruisers and a fair amount of bumped-out diamonds. Chairs 9, 22, and the top have a decent selection of chutes and cornices, and you can find some trees on the Eagle side. Santiago Bowl, when open and fresh, is fantastic. Chair 5 and below offer some nice natural half-pipes. When it dumps at Mammoth, the powder is not Utah-dry, but much drier than Tahoe’s Sierra cement. I saw someone say that Mammoth over-reported their snowfall this season. I’d have to agree, but at the same time, that’s not really a problem as they usually get a ton.
The terrain parks are some of the best I’ve seen. There are 2 permanent parks, an intermediate and an expert, a massive half-pipe, and a third park that routinely pops up for beginners. The two permanent parks are serviced by their own lifts. Mammoth may be the most boarder-friendly mountain in California, with minimal long, flat traverses or uphill sections. For those who care, the ratio of skiers to riders is 50/50.
Mammoth is very family friendly. Ski schools, daycare, camps, you name it. The instructors are patient and friendly. One word of caution, if your kid has some experience on the mountain, you may want to slightly exaggerate their skill level as the classes tend to assume your kid has no idea what they are doing. The flip side is because the mountain caters to families, you do run into a lot of inexperienced skiers/boarders that are overmatched on some runs. Expect a handful of near-misses, clueless people floating around trail junctions, and people stopping in the middle of runs.
The nightlife is good, not great. It’s not Tahoe, there are no casinos or super high-end restaurants. There are a handful of nice bars and restaurants at Main Lodge and Canyon. If you want more selection, you can go into town. Best bar is the Clocktower Cellar at Canyon Lodge. Amazing whiskey and microbeer menu.
Okay, here’s the rub. Aside from being expensive, Mammoth can get really, REALLY crowded, especially on holiday weekends. As with most resorts, this disproportionately affects the blue-green crowd and the lower lifts near the lodges. If you stay high, on diamonds, and out of the middle, you should be okay. You can also feel the natural ebb-flow of where most people are on the mountain and go to the other side. It’s big enough to handle the crowd, but the chances of finding untracked late in the day are slim. Last on the cons, it can get windy. Not Breckenridge windy, but enough to get a sudden white out. If it persists, the top will be closed, condensing everyone in the middle. Despite this, Mammoth is good enough and close enough I keep coming back every year.