I stayed for three nights and could not be happier! Satoshi-san and his family are lovely, friendly people and made this a very relaxing experience. I recommend staying in the more traditional rooms with tatami and futons, it was very comfortable.
Note that, if you are a westerner, you may not find it to your liking to have a shared restroom and and bathroom. Please do not be put off by this, it's part of the experience and you can have 30 minutes of the bath all to yourself if you like. This isn't a Ryokan, more of a ski lodge, but it's much more intimate and cozy than some cold Tokyo hotel!
Upgrade to get the breakfast in the morning, it's worth it. Satoshi-san is a great host and will probably offer to pick you up from Echigo-Yuzawa station. It's within walking distance of Ishiuchi station, too, if you choose.
I stayed at the end of summer and it was outside the ski season. I don't know what it would be like when it's busier, but I sure had a good stay.