Dude-
I can't say for sure what you are thinking, but I know I was there. I had a lot of questions for myself and concluded I wasn't joining for the right reason, so I opted out.
Based on my experience here's what I would say to you: Think about this for you, and for you only. Don't read other people's context's into this situation. (Ironic that I am telling you this, isn't it?). If this is what you wanted, think about why, and remember that money doesn't mean shit, a good job is doing what you want.
Oh, and I'm reapplying if that gives you any idea of how well my decision settled with me, and I'm pretty sure that I won't get my SNA spot back, but I have to try.
You can PM me if you want.