I met my ex on a dating site and we were together for three years and for a good deal of the time extremely happy together. Then again, he's my EX. I'm pretty dubious about the other people who I've seen on that same site, though...
I have tried it and from my experience a lot of people on these sites are single for a reason. There are a few good ones, though, and if you are willing to take the time to sift through the rift raff and become good at spotting who they are it can be worth it.
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