“Open” relationships

Would you get involved with someone who is in an “open” relationship with their wife? To be clear, we’re talking about being adults about it (not a fling or being super clingy/immature). We both have our own families but I’m recently separated and we met on a dating app. He’s been very upfront about seeing other women regularly, and I’m not looking for a long term serious relationship. But I don’t know if I can do this other extreme either. We have a great intellectual connection, and yes, also quite an intense sexual attraction. Just not sure if we can keep it platonic for long!

* Maybe “open” relationship is the wrong choice of words. They have an understanding that they both see other people, but agreed to stay together for the kids.