I went once and it was amazing. The staff is so friendly and the food is great. We sat on the balcony and watched Fantasmic. Definitely something I would splurge on if I won the lottery and lived close enough to enjoy it often.
The members who invited us said that 33 has special events for members. In one, they took a group of members to Splash Mountain and closed it down to other guests. After the ride, they flipped on the lights and had an imagineer talk about the ride, then all had dinner back at the club where they were given a gift-- a really nice Splash Mountain frame with a pic of them on the ride that night.
Where the Club seems to excel, IMHO, is at being elegant and truly special without being stuffy or snobby.
I do have friends who were invited by their company who said that they did not have a good experience (food was not up to par, service was very rushed and unfriendly). All I can say is that it was probably an off night because I have never heard anything else like that at all.