Pretty much been there done that.
Beside the amazing view and the experience of an active volcano the skiing pretty much sucks. Some guys call it a mini golf place. Very short steep areas followed by very flat stuff. You can hike to the better areas but still it is a very long way back to the base after each run and the "Rope way" Tram is only running every 20min. If you hike to the very top of the volcano you get a nice steep run so if you are into BC a lot you should go there and by a single ride ticket for the ropeway. About 1000 Yen for a ride.
I would go back on a real blue bird day just to hike to the top, enjoy the view and ski the face into the volcano one time but otherwise this resort is a no go for me.
How To Get There
Almost 2h drive from Furano
Moderate for the Tram but big time in terms of visibility
Other Resorts in Japan