I require registration for my Adwords hits to my search page. I've tried it both ways, and definitely get better results with it required (better return for my PPC $). I feel that if they won't register, then they are probably not very motivated prospects. All registered leads go into my automatic drip system.
I'm using our free local MLS IDX which is not nearly as flexible as the commercial versions like IDXpro. I'll probably switch soon and then may get more selective about what triggers a registration requirement.
There's another good discussion on this topic at:
https://www.reliberation.com/blogs/mfarm...e-question.aspxI should note that I don't require registration for those hitting my home page through google search or direct link. Only PPC hits require registration.