I've been meaning to do this for a while. Since this is the hot topic I'de like to hear/see what everyone is doing and finding.
I've been running the GGB's and have had great success not only on customers boats but mine too. They cut the db's down low enough to be legal or close enough to it to keep you from getting a ticket or kicked off a lake.
We've seen NO hp loss both in the water and more importantly on the dyno. We ran my own naturally aspirated engines with and without and got a clean peak 675hp.
They're well built and have no packing that's going to burn or blow out. They look good and still have a good rumble at idle that lets everyone know you've got something that means business!
Show me what you've got guys!!!
O'Neill Offshore Marine