Once you start... you will never want to leave lol. Admittedly and somewhat regretfully I agree with the comments above about risk. I've dove a lot of the cenotes around here and the tours you are talking about are generally shallow but overhead environments nonetheless and some are circuits while some are drop off and pick up in other areas.
If I wanted to argue the other side I would say that it depends on you. The main thing is that you should be a confident diver with good skills, especially buoyancy control. The problem that I see with most tourists that come down is that few are good divers, they are more vacation divers looking for an adventure. Now I get it, I really do, but the consequences are real.
In my humble opinion the risks for the tours I'm thinking of are minimal but... it's a personal choice and there are so many factors.
If you're interested in cenotes then you don't need to do overhead dives to explore them and cavern dives are really quite beautiful.
I hope this helps, I realize that my advice seems to be all over the place. PM me if you want more data, I'm literally in cenotes and caves 2 to 3 times a week.