Has anybody here ever hooked up just to have casual with an ex? Did you regret it or was it worth it?

Hello, have any of you ever had a sort of call (or calls) with an ex just for casual ? Not to get back together or anything but just for ex- or whatever you call it. Was it good, did you enjoy it or was the emotional baggage of the relationship too much? Would you recommend it and if yes what precautions would you recommend taking to make sure things don't get too personal again? Also had you found that the was better than it was when you guys were actually together or that your ex learned some new moves or was more liberated and willing to try new things, positions, etc? Please give as many details as you can and thanks for your answers in advance. :)