Holes in the concept
I have seen season 1 and 2 and I truly find this concept very interesting, and I also find it is a teachable moment. But I think the producers might do more to make people understand that they are LITERALLY each other’s ex when this takes off. It should be a demand that they block their ex while in the trial-marriage, and it should be against the rules to contact your ex until the procedure is over. One person I misunderstood a lot from the beginning and whom I really started to respect was J.R. from Season 2. He really understood what to do when the ex came knocking. He simply said you are not coming in, because that is what a true husband does when the ex comes knocking.
Those in the show who makes all sorts of boundaries that you would not do in a marriage hasn't understood the concept. Sitting in the couch and lying in bed constantly talking about your ex and that you are still loyal to your ex is utterly disrespectful to the person you have literally married for 3 weeks. That should mean out sight out of mind. How would your coming wife or husband think if you constantly worry about how you ex feel right now. If that's how you are going to waste your time in a trial marriage, don’t sign up for such a unique experience that could benefit so many other people who would take this seriously.
The hosts should be stricter in my opinion and make it strictly forbidden to contact your ex (the person you arrived with) or anyone in their immediate family.
One thing I believe should not be part of the experience that ruins it a little is the boys night out and the girls night out. First of all it seems like the least serious part of this experience, because it seems like something the producers want because it always create drama when you put a lot of jealous people in one room and serve them alcohol ad libitum. It seems to be more to attract viewers than to benefit the participants. This could just as well be done after the experience is over in a more sober setting. Besides it is in my opinion in stark contrast to the entire idea of simulating a genuine marriage. In a genuine marriage your spouse don't just go out with your ex and get drunk, and tell your ex what is wrong with them. That shouldn't be part of the show. On the other hand I truly love the introduction to family and friends. That really gives a genuine insight in the person and their background.
I will also see S3 and S4 and I hope they make a little stricter rules against keeping contact with your ex.