I got the Accelero Hybrid before learning of "The Mod" and I had expected that the built-in fan in the shroud would actually push air across the PCB to cool the VRMs and RAM as the marketing claims. The fan part I believe is somewhat of a gimmick as the cooling block severely restricts the air from reaching the VRMs on my MSI GTX670 reference card (would probably work better on a GTX680 as the VRMs are right where the fan would be). I even built the recommend fan shroud (only for short cards) out of plastic to direct the airflow but still no luck.
On the upside, the block does perform as expected on the GPU keeping it at 54C maximum under full load. If I was to do it again with a closed loop, I would definitely go for "The Mod". I ended up keeping the stock VRM heat sink on my card (the heat sink supplied are pretty small and I didn't want to permanently glue some heat sinks on the card). I also modified the shroud to clear the stock heat sink then ghetto tie strapped a 120mm fan pushing air up at the card right onto the VRM heat sink (you can see pictures of it on my rig page linked in my signature). All in all It works good but it was more expensive, so your doing a good choice going for "The Mod".