For those of you who use one with a heart rate monitor -- how well does it work? Do the numbers jump all over the place, or are they fairly consistant? I'm thinking of getting one with the HR and chest strap.

Do you ever find yourselves exceeding your recommended maximum heart rate (such as on a steep hill)? If so, what do you do? Just don't worry about it and keep going, or do you lighten up and drop back down? Does it scare you when you see your heart rate getting really high?