There is nothing wrong with the formula. It all comes down to the tenants involved and what they are willing to do and not do. I too am not a fan of couples but a couple like Anna and Alex who are open to partying and engaging sexually with others is never a bad thing. Having said that, I must express disappointment in this decision to move Bobby and Nina into Volga (I'm no longer referring to him as Kojak since he now has an official name). I was under the impression that Volga was going to be a testing apartment for potential tenants or people who just wanted to get a feel of living in a cam house, which would have been wonderful, but obviously we're not getting that now.
The tenants are allowed to have whatever guests they want to have. Not every single person that enters an apartment is someone set up by the voyeur managers.