For 1, I probably don't notice if the author doesn't mention a beta, but if the author specifically says there's no beta (even if it's not "omg lolz this sux no beta" but "i was in a hurry, so let me know if you catch errors), I'm more likely to skip it.

Five or more betas doesn't make me question the writing, but it does make me think the author might be really anal retentive. Not that I'm not.