Locking on page load vs. Locking on download button click. Better conversions on click?

Hey guys. Just wondering if anyone has tested both of these thoroughly. I'm wondering if locking on click will increase conversions, and if it is a significant increase.

Please no guessing here, looking for real data proving one or the other.

Cheers,
xxf8xx

Why don't you test it yourself and tell US the results?