I don't know about "trying out" the TC-4 but at leat I can say that I have one running in my system right now
AS for its performance........................At least it didn't go up in temps. My first block was a BE Cooling "Jagged Edge" waterblock and it worked fine. I moved to the TC-4 for several reasons: looks WAY cool, uses MB mounting screws vs. clamp that the BE block required, used something to "sturr up" the water, and it is a "snake" design (AKA water goes in the bottom and always moves up to the top and then exits).
Both the BE Block and the TC-4 hold a 6-7degree delta from my case temps.
I think my radiator is maxing out instead of the block so I am planning on adding a modded Black Ice II to my rig to get my temps down some more.
Otherwise the TC-4 looks like a real winner.