I was considering another extension like this one, but their free version was buggy, and when I posted on their support forum about it, no one answered me. So after a week I gave up and decided to purchase this more expensive one. But boy am I GLAD. Right after installing it, I had a problem with the captcha not displaying properly and support got right back to me, explaining how the problem was being caused by my template. Not only that, but they helped me fix some other css issues with my template. So I am really a happy camper.