I've been, but it's a while ago.
I actually like the place a lot. The ambience is different - more relaxed and often more personal. They also have different theme nights than all the otheres - like the bi night, and it makes up for a truly sex positive space.
That said it's rather small, so it's a bit hit or miss if there's anyone you mutually get off on. Unlike bi places abroad theres no gazillion dollars for single men, single women free bullshit. As there is no sorting of genders either, there's usually a clear majority of men. But as it has this relaxed atmosphere it usually works for the women/couples there too, and the ones that come are there to fuck.
On bi nights expect most people to wear condoms, at least for playing with any women.
Unfortunately I'll miss you by a few days, as I'll be in Berlin from the 28th.