I have personal limits, boundaries, as it were, but they mark the point whereby my needs aren't getting met and so I have to change things in my life. I.don't believe in attempting to control someone else in order for them to be who I need them to be. My partner(s) are free to do as they wish with the understanding that some of their decisions may affect the way we interact. It might affect it negatively. Being free to do as you wish doesn't negate the fact that I expect due warning when something has happened that will change the way we interact. My partner is free to go bareback with anyone he wants without asking, but if he did and then didn't tell me before we had barrier free sex, I would feel betrayed.
So yes, I do have open relationships without limitations. That's why I do this poly thing: it encompasses all the things that I think are fundamental to healthy relationships in a way that you are forced to practice if you want to consider the needs of everyone involved. You have to trust your partners and their partners when you don't limit how they can interact. You have to respect how people need to interact differently in order to form emotional attachments. You have to acknowledge the needs of your metamour if you want partners who focus on maintaining relationships and you don't want to enforce protocols that go some way to guarantee that they do. Putting down limits and boundaries to control the behaviour of others seems like an attractive way of protecting yourself, but really it just sets an undesirable foundation for polyamorous relationships. One that assumes the people involved are going to behave unethically.