Pretty Sure They're All Wrong

The underpants guy from the bar came over for dinner on Friday night and didn't leave until Sunday night. He's hilarious, we have a good repartee... the 13 orgasms he gave me didn't hurt, either. He came over again spontaneously on Monday-Him: "I want to see you but I didn't want to bug you" Me: "I wanted to ask you to come over but didn't want to bug you!"- for another dinner with a few roses in my favorite color and a bottle of wine.
He got kind of deep, telling me about his family and how his previous relationships are affecting how he acts now, but he was still very sweet and very funny. I could see being pretty happy with him, but he has an immature side that's about as big as my don't-take-no-shit streak, which looks like a self-fulfilling "this ain't gonna work out" prophecy to me!

If you noticed, I'm not my usual excited and dirty-detail-y self about all of that. Check on what I found in my facebook inbox this afternoon: one of Guy's [that's my roommate, by the way. Not sure if I've used that name before or just refer to him as Roomie's boyfriend. Whatever] friends asked me if I wanted to hang out sometime in a totally awkward but pretty cute message. He's cute and he's a really laid-back type of guy, plus I can't deny that I really like that HE asked ME out.

Currently hashing out on facebook chat with Prof Science. Highlights-
JS: i kinda feel like im stuck between something that has potential to be awesome if i work on it, and something that i know will be just nice

without me having to TRY to get the guy to be who i want to spend time with
...which kiiiind of means i dont have a problem to begin with
Prof Science: it's only not a problem if you're looking to take it easy and be comfortable for a while. if that's what you want, you totes deserve a good dater and some relaxation
the problem comes up when you know that something is already on the way to being amazing with someone else

JS i tend to shy away from the "good" guys bc i just figure they wouldnt like me since im such a bro

yknow, like they'd prefer a girly girl

id love to have a boyfriend i could rely on, but i just kinda aim low and fire often

Prof Science: if the bad guys did the good guy datey thing that would be kick. ass.

Prof Science: mr "i'm awesome in bed, romantic, funny, and we have a connection, but who knows what i'll be like in the future?"

vs

"i seem sweet, and we could double date, but it's a complete mystery what could happen."

What do you guys think- The guy I'm having an awesome time getting to know, but who could turn out to just be kind of annoying and a flash-in-the-pan, or the guy who is sweet and nice but who could turn out to not be into the type of girl I am? [Prof Science is Team Nice Guy, which makes sense because she's a good friend to me and doesn't want me to be with a guy who has the potential to suck.]
I know I have to see the underpants guy at least once more because he left a book at my house, but I obviously don't want to be dating two guys at once because that just confuses me and I end up ruining everything.
I accepted the "hang out sometime" offer from the nice guy and gave him my number so that he can contact me telephonically.
And we can't forget about Saturday. Even though he's not the most available guy out there I can't pretend like I don't like him.

I know, I know: How many of these posts are you guys going to have to slog through before I either find someone that makes me a happy lady/ give up on men entirely? I'm guessing a few to several.