Is pre-marital sex good or bad?

Recently I found myself in an odd discussion about the benefits of pre-marital sex. For some strange reason I allowed myself to stay in a conversation with a overly religious individual, this act was my obvious first mistake. According to this person god feels a need for us to abstain from sex before marriage.
Now you can probably predict what I had to hear next-the whole virgin Mary story made a appearance. In my opinion things didn't go down the way the bible depicts. Mary didn't have "immaculate conception", but in fact she must have conceived a child from someone other then her partner and needed some kind of excuse in order to not lose her husband Joseph. In a way Joseph is the king of all gullible people out there.
Now, after listening to all this foolishness, more foolishness followed. The flurry of advantages came into the conversation. An obvious way to prevent catching a STD, I just figured a condom would solve that outcome. Abstaining would make you and your partner feel closer. I believe there were more examples, but this is the moment that my mind faded out.
I always compared sex to buying a car. Don't you want to try it out before you purchase it. You want to know if your the right fit for each other and sex plays a factor. At any rate, I loath talking to people who are extremely religous.