Is it long enough?

I have been talking to this really nice guy, who has a lot common with me. But there's one thing that's just making me think more about it all, and thats the fact that he only split up with his ex-girlfriend of six years four months ago. He doesn't really talk about her or anything, all i know is that it took me only a month or so to get over a six-month relationship, but I know guys think very differently about these things to girls. Does this seem ok or do you think I should possibly give him a fair bit more time? Or is it just a case of taking things very slowly, probably like you should do in most relationships, not that I am very good at it, if the past is anything to go by!