Stevo, I don't really think it's a self esteem issue. If my self esteem was low, then I'd be worried about my ego getting damaged from getting dumped. As it is, if it's what I wanted anyway, it doesn't hurt me.
Understand this, BUT OP is worried about what people will think of him if he's doing the dumping. I guess, if we're going this route, there's two sides to this. What will people think of you if you're the one being dumped, and will people think of you if you're the one doing the dumping.
Good points here if you think about it. Depending how you look at it, as far as your image is concerned, neither one is beneficial, or they're both beneficial.
As a generalization:
Alpha (bad boy) - does the dumping.
Beta (nice guy) - gets dumped.
And this will be how you are perceived. Some guys fit, and like, the nice guy roll, and hate being the bad guy. But sometimes you have to be the bad guy - and understand that it's okay.