Most of the guys below have told you that most men care about the number instead of the who. In this situation that would be incorrect.
If these guys are friends, the first guy has, and will always have been with you before your new guy, and most likely that will be too much for the new guy if they're good friends. Men are very territorial, and to have a girlfriend that has slept with a ftiend would eat at your relationship over time. This is just my opinion, but it's based on our psychology and what I've seen in real life. If I was you, I would avoid the drama and stresses this situation would cause.
It always gets me how people say "There's nothing wrong with hookups. One night stands are fun!" It might be true, but the past always comes back to you. Good luck.