Who cheats more in a relationship/marriage, men or women?

Guys, can we have an unbiased, say-it-as-it-is discussion this morning?
Who cheats more in a relationship, marriage? Men or Women? What do you think?
Someone said this:

Most of the relationships that break because of cheating happen because the cheater is a girl and not a boy.

Typical Scenarios: 

1. Girl not happy because guy is over protective. Let's punish him by dating someone else who is flirting with her.
2. Guy is in a different city. There is no one to take me to different places, there is no one
to pamper me, oh the guy in my office flirts with me and also takes care of me. I think he loves me. Let's date him. My boyfriend is surely not going to know.
3. I had a fight with my boyfriend today, this other guy is pampering and supporting me. He is so nice. I should date him. And i start dating him.
4. My boyfriend can not earn enough to keep me like a queen. I know this other guy who earns a lot and also seems to be attracted towards me. Lets date him. 

And all this while they forget to breakup with her boyfriend. This is cheating and girls do it a lot, mercilessly and guilt-free.

Another person said:

Biologically speaking, men are more likely to cheat.

Men can typically impregnate women every few minutes, while a woman can conceive only a limited number of times in her lifetime. Worst case scenario it would be every 9 months before menopause.

As such, men are more likely to cheat than women.

Read what this other guy said:

Both are equally likely to cheat.

Men are wired to impregnate every subsequent woman they can find.
(even if it means leaving a previous spouse)
Women are wired to to get impregnated with the best man they can find.
(even if it means leaving a previous spouse)

But then, we are humans and can choose not to follow our lower, primal tendencies.

What do you think? Which of these 3 people do you agree with?

Let's have a great discussion, guys