Is the sensitive guy whiny?
If so, then the jerk.
Yup. Nailed it.
"Sensitive" is not always a great characteristic. I prefer "empathetic" and "caring." Sensitive guys write really bad poetry, show up at places when you're with another dude, and think even the slightest change in your mood is about something they did.
Also, what's the fixation with cars? I noticed it in the Bunz thread too. I'm not in highschool. I have a car. I don't need the person I date to have a car. Having a car in a big city is stupid impractical, too. You don't want to know how much I had to pay for parking permits in Boston. And if the jerk guy's car is so nice that he doesn't want to mess up the paint, then I think he's probably mismanaging money because he could have bought something cooler, like a beach house (and that should be the selling point here, not his car), or he has a really scary bad car with a crap paint job that can't handle a little rain. Seriously, only fifteen year olds care if the person their dating has a car or not.
Oh and now, for the kicker:
This is why men are jealous. Motherhood is always certain, fatherhood always a mystery.
Concealed ovulation is an evolutionary godsend. (seewhatididthere?)
This man speaks the truth. Women are jealous too though. We're more concerned about "emotional" cheating though than having a partner sleep around. If he's just banging other chicks you aren't losing resources. If he becomes emotionally close with someone else you're losing resources if he's doing nice things for her like buying her lunch or fixing her car, and you run the risk of him leaving you and you get nothing.
This of course is a lot of generalizing. Obviously every person and relationship is different and we've changed a lot as a species sociopolitically, but our genes haven't quite caught up with that yet.
If you marry the HOT woman, then why do you need to cheat??!!!
Maximize reproductive opportunities.
Plus you can't be certain the hot chick isn't cheating on you.