Some people prefer Match.com to e-harmony because it is less structured, and, truth be told, it has a younger, glitzier image than e-harmony does with it's doddering founder and spokesperson.
Match.com also has made the clever marketing decision to allow 'window-shopping' for free. They send you your matches at no charge, upping the chances that you see someone twitterpation worthy, and are then inspired to sign up as a paying member. E-harmony doesn't allow you to view other members until you've paid the fee. They lose some motivation points that way.
Rather than list another paid dating site, I'm going to share my personal insight into the online dating phenomenon. If you really want to be with someone, and you want to find people who really want to be with someone, these sites will probably provide what you want.
But- you might ask yourself, what's the hurry? Is it so important to find someone that really wants to be in a couple, or is it more important to wait and find someone who really wants to be with me?
Maybe the best way to meet someone, be it online or in real life, is to just be yourself and let things happen ...