Dude, I've met a lot of women off dating sites. A LOT of women. The reality is, the best approach is to look at the people, decide if you're mutually attracted on a physical level, and then meet in person straight away.
You can't get to know a person online. What you're getting to know isn't who they are. It's a strange brew of how they see themselves and what you'd like them to be.
The more time you spend "getting to know" someone online, the more attached you'll become to something that doesn't exist, and the more angry you'll be when you're inevitably disappointed.
I've met hundreds of women through dating sites. In the beginning, I spent time making my mistakes with women who lived in a different town, so I could experiment without having to face the consequences of my mistakes at the grocery store.
I've slept with so many of them that I literally got bored with it. I haven't been on a dating site in over a year. But, before I called it quits, I honestly had guys I worked with come up and ask me what my secret was, how I managed to get SO many dates with SO many good looking women, because they knew that I was meeting at least one new woman a week and sometimes more than that, and getting laid all the fucking time.
I'm single by choice, because I decided I deserve something better. But make no mistake, the things I say are true, and I learned these things through vast amounts of experience.