I can say that this place is unique unto itself. The M does a good job of hiding it down in a cubby hole to make you really feel like you're walking down into a wine cellar. But honestly, that walk is a killer if you're a lady in high heels, which I was. They should at least offer an elevator... for safety reasons. Wine cellar + drinking + stairs = hummm....
Anyway, the atmosphere is exactly what I'd look for in a wine bar. Dark lighting, cushy seating, and a feeling of coziness to drink wine and have conversation. This place does all of those things. Albeit I was here on a Rock & Roll Wine night and did not actually purchase any wine I have heard the system of actually getting the wine is unique. Being that you purchase a card and then can go to each of the "wine stations" and get your own tastings.
Personally I enjoy having my wine poured for me and brought to me, so I'm not sure if I'd actually go back and take part in the process. There is a bar here though, so you can sit and drink if you prefer. There is also food. Extremely overpriced appetizers. Seriously - if you're hungry, just leave, go to another place in The M and come back.
Overall, this is an okay establishment. Definitely not one of the bests in The M for sure.