We went to take the kids sledding. A long way to go I know but my wife was adamant.
We did not find a really good place to sled even the 5m height / 30m run at the left hand side of the children's play area (flat) in front of the restaurant by the second upper car park was enough for our three year old. And ramp into the same area from the direction of the top of the mountain was more than enough for our 7 year old (who wiped out in a snow-less area). Had we not used the lifts then playing around in this area, using the toilets, their canteen (we brought our own tea), and car park would have been completely free.
Additionally, since I saw a cheap ski set, I took to the slopes and the lower central lift was great. I am a beginner (third time on skis, the other times 17 years ago). I went down only twice with my skis mainly in that beginner V shape. The lifts are easy to board. The snow is pretty thick and not hard. The run was not as wide as I would have liked so that I could really avoid getting in the way, but the good people coming down from the top (way way up in the clouds) were plenty good enough to avoid me, and there were not so many beginners on their backs. I think that a good time was being had by everyone. I certainly had a good time.
Drawbacks. It does take about 45 minutes from the expressway even when there is no snow on the route there. Take the longer, non-scary route (see other reviews). Even the non-scary route had the occasional obstacle which would cause problems in the event of oncoming traffic. The lower car park was full. The upper car park was nearly full. So perhaps sometimes people are turned away. It seems ridiculous that the limiting factor should be car parking space since there is lots of space that could be turned into car park, but as with all things public in Japan, efficiency is not a priority. But these folks are not national public employees, so they do not have that supercilious air. They were very nice and friendly.
The only other times I have been skiiing are to the more famous places in the same region (Geihoku and Daisen). Osokoran seemed generally much better. The name (means "scary") and the lack of marketing is the only thing that prevents it from being Ski Mecca in Western Japan.
No specific date.
Snow condition on visit:
Thick carpet, *slightly* slushy or soft towards evening. 110cm according to their web site.
Things I liked:
Loads of runs, lots of snow, friendly, relaxed atmosphere, not-steep at bottom, easy to ski
Things I didn't like:
Distance from motorway, lack of parking space, lack of cushioning on hard things next to run (perhaps that is universal), shuts at 5pm