Pretty ring. Had to manually delete the "http" stuff in the link to get it to work, though.
I think you're right in that the channel set has metal around the sides of the stones so it protects the stones better. But as to which is more secure, well, there can be variation. So long as something is well made, that will always be more secure than something that is more poorly made. I've read of ladies here who've had prong set bands they've worn for decades with no stones chipping at all. I wonder if the stone size also has something to do with it. I have a 2.5mm prong set band, and I really feel like I'd have to take that thing under a steamroller to do some serious damage to it. The stones don't seem to be easy targets, and the prongs are very thick.
Obviously, I'm really happy with the eternity band I bought. It didn't seem to matter how many stones were in a band, because my knuckles are bigger than my fingers every ring seemed to want to spin. Problem solved! And I hope yours will be too!