Stayed here 6 nights. Nice traditional room with western beds, quite low though. Firmish mattress, I think they were pretty old but still OK comfortwise. Plenty of room compared to a couple of hotels we stayed at in Tokyo so that was a big positive. It's location is just about perfect, just a brief wander up the hill to Yu Road and you're at the slopes. We took a stroll around the whole village one day and we're so glad we picked Jonnobe.
It is however getting tired and is need of a freshen up.
The breakfast is...interesting! Sort of across between western and Japanese food buffet so you can load up before a big day skiing/boarding.
One negative, I'm quite sensitive to to dust and our room was making my sinuses go wild, so it was clearly dusty or the tatami mats may have been releasing tiny spores of whatever. Fortunately the COVID-19 outbreak had made me get some masks so I just wore a mask whenever in the room, even sleeping. Peculiarly, a couple of days weren't as bad as others. I can only assume that some cleaning and vacuuming had been done to reduce airborne allergens.
The onsens are awesome. A soak after a hard day on the slopes was exquisite and invigorating.
And not sure if this is a positive or negative, Nozawa Onsen seemed to be full of fellow Aussies! Both visitors and staff at various facilities i.e shops, food outlets, accommodation places etc. Good to be able to communicate easily but it sort of detracted from the uniqueness of travelling.