I would agree that it would definitely take more courage in the beginning, especially since their only experience is thirst and they would only be able to hope and trust in Carlisle’s assurances that things would get better. The “thirst” thing in general, though, is always going to be a different issue than Edward’s reaction to Bella, which never really abates.
Your point is well taken in that the quenched thirst of the vampires in general is…not that bad once they get used to it? At least as long as they feed regularly? We know that there are stages that get progressively worse between feedings, and that it can get to the point where it literally feels like fire in their throat, but that they often can go up to a couple of weeks between feedings.
I think there are several factors at work, though. First is the baseline sensation of being fully quenched, (i.e., just how bad is it at that point?). From what I read, the best-case scenario is still a dry, raw feeling in the throat?
You then have the time elapsed factor after feeding, which we really don't know a whole lot about, except that things get progressively more painful (although still not so bad after two weeks??? Edward’s eyes were black when he first met Bella, how long does it take before the throat feels like it is literally on fire???). And then there's the vampire’s general attraction to blood exposed or non-exposed, the general attractiveness of the blood itself, the potential “singer” or “Bella” effect, and the general self-control developed by the vampire. I’m sure there is a calculation somewhere in there. Most of the factors are multipliers against each other, with a dampening effect based on general self-control.
As far as Mike’s pinpricked finger goes, I would suggest another possible interpretation, and I am going to omit the most obvious, which is that Bella is so overwhelming that Mike’s blood is irrelevant. Edward may have been able to brush it off due to his self-control effectively nullifying the blood’s effect on him. Being able to disregard it, though, is different than saying that he isn’t thirsty or that drinking Mike’s blood wouldn’t have quenched whatever thirst he had.
Anyway, maybe the Illustrated Guide will answer some of this in greater detail.
[I'm trying to stay on topic here]
P.P.S. Sorry, further clarification needed. I read the basic difference as the baseline thirst of the veggie vampires is always higher than the red-eyes, but their attraction to human blood is diminished the longer they abstain. The red-eyes can feel more fully quenched, but they are most comfortable after feeding and then removing themselves from the presence of humans. I think that’s the way it goes, that veggies always suffer to some degree? I think some more detail is needed, such as the level of pain involved for a veggie after feeding, with and without the presence of humans, and then the same thing but after a time elapse of about two weeks. And is it the level of attraction that diminishes, or a function of self-control, or some combination of both? Does Carlisle feel pain, or is he able to just compartmentalize the whole thing and effectively ignore it?
"It will take an amazing amount of control,” she mused. “More even than Carlisle has. He may be just strong enough…the only thing he’s not strong enough to do is stay away from her. That’s a lost cause.”