NewPartner introduction - how long did you wait?

Currently 18 months post-split, starting to date someone seriously. My kids are 6 and 8. I know the advice is 'wait at least 2 years' but tbh I'm not sure that's realistic for me. My ex is already introducing guys to the kids pretty casually. What's your actual experience? How did your kids react? Did waiting longer make it easier or does it not really matter?