Pros: LOTS of snow, good incline, not too crowded
Cons: Often snowy (not sunny), Maritime conditions, limited nightlife
Great terrain, world-class waist-deep powder, beautiful scenery. The mountain provides surprising variety in terrain, with good steeps and a few glades if you know where to look, however it can be quite dangerous if you don't know where to look as they have a lot of often-buried metal retaining walls off the main slopes. There was ~40" of powder on the slopes when I visited and there was little grooming done. It made things a bit cruddy in the afternoons once things had been chopped up, but mornings were full of face shots and beautiful lines. It snowed more or less non-stop for the three days I was there, and was one of the most memorable experiences I've had. There are tons of accessible cafe/snack shops on the mountain, however the hill's big enough for them not to be too in-your-face.
In terms of off-piste, there are many semi-in-bounds options, however the avalanche risk in this region is tremendous. I fell in the powder, dug myself out and then realized I was in a moderate incline slide, which I thankfully was able to advance beyond. This year there have been 4 fatalities in the valley due to avalanches by January, and they were in-bounds at a local resort. The food in the area, as in much of Japan, is absolutely fantastic, and the people are by and large extremely polite and hospitable.
It's a quick trip from the Narita airport (JR express to tokyo station - 45 min, shinkansen to nagano - 90 min, bus - 90 minutes) and you're in Hakuba. If you land at 5pm on a Friday, you can make it all the way to Happo the same night.