Should I trust a man that is friends with his ex?

So I'm currently talking to this guy and he is an extremely nice person. He treats me with respect and he shows me how a queen like myself should be treated . We don't live on the same island. We are about 40 minutes away from each other. We both visit regularly and he tells me everything( well so I think).. I trust him to a certain extend but he and his ex broke up like 2-3 months ago and they still friends. Sometimes he tells me she asked him for a ride and he is going to pick her up, which is fine cause I trust him a little and plus we not In a relationship as yet.. But should this be something to worry about? He also told me when we consider making this official he will have to cut off everything with her.