I really don't like the concept, I am not social as a rule, I have a few friends who have my exclusive attention, I don't switch people or do parties etc. So casual sex is an extension of the idea.
Also, in regards to safety, nearly zero chance of infection isn't much comfort to the people who fall in that last 1%, and since there's no way to be sure.... Also I trust no one, so claiming you are safe does me little good.
Now on to my favorite part, the part where my opinion is promptly hurled from the nearest window.
I'm a Christian, and as such I believe its for marriage, I am not gonna force people to do what I say, the acts and the results thereof are theirs. However, I would be seriously challenged if a girl I was interested in had been around. It would be a major issue to me. Also a relationship can be viewed as a claim on a person, I don't even share my games very happily, I won't share my Significant Other.
Few minor points that I wanted to shoot down.
"Why shouldn't we give in to our base urges?"
Because those include killing others(watch any group of territorial animals), which is still wrong I presume? Being natural doesn't make something right.
"All those high and mighty people who think...."
Because if you are on the Free Love side of this its just fussy fools blathering on, but if you are otherwise, it provokes disgust and it is WRONG.
"Ain't your business"
Is Too, She asked....