The majority of my relationships have been open, and my partners and I felt comfortable and loved, and everything worked fine as long as everyone was honest with him/herself, and each other.
There was one man who got his feelings hurt, and I'm still not sure whether I should blame myself or not---he told me that he was okay with everything, repeatedly, but I could see that he was trying to fool himself. I let him be his own judge about when to leave, but he definitely tried to convince himself that he was okay for much longer than was necessary, and he wound up quite hurt. I feel really badly about the whole situation with him.
But for the other partners over the years---basically if you have the capacity to be honest with yourself, and you are a)not instinctively very jealous and b)able to discuss and work through any jealousy that does crop up in spite of your usual nature---lovely and enjoyable.