I guess I can say that I am pretty much a fixed blade guy. However I have tried mechanicals (Rage 2 blade) and although my experience is limited with the one deer I did take with them I was impressed. I did shoot from a tree stand and had a complete pass through (63# @ 28.5" 420 gr arrow). The blood trail was short and very easy to follow even though the tracking was done by flashlight. Blood everywhere at least a foot wide in most places.
I'll be anxious to see a report on these Dead Ringers - good or bad.