Accepting a proposal of someone who commited zina

A proposal has come for me, and he has been very honest with me. He is older than me by 6 years- I am not sure if that is a problem Islamically. He has told me that he has had sexual relations with a non-Muslim which he was with for 5 years. He broke off this relationship and went out with a Muslim girl whom he also had sexual relations with. I was more shocked about the Muslim girl than the non Muslim girl. Once or twice I tried to voice my opinion, maybe I wasn’t tactful enough, but he seemed to get angry.These relationships are now over. I am a virgin. He seems to be Islamically inclined now and reads Salaat and gets involved in community Islamic projects. I’m not sure if he has repented or not for his sins. Should I accept or not? Islamically what should I do?