They are advertised to take 850 hp and 850 lb with up to a 15k boat. Anyone running them that could give me some feedback on them?

Look at the Max Machine Worx's drive. There has been lots of talk about issues with the Bmax.We have The Max Machine on our Sonic 386 and are running 800hp/836+lbft of torque threw them.

Runnin B-Max here on a 42' non step Fountain...800HP a side at the moment.
No problems...remember this, you can't run the Merc lube in them or they will burn up.

Running Trip 600 In A 37 Ol. The Only Drive That Will Hold Up. Boat Weight Is 12,000 Lbs. There Are No Issues With The Drives Any More. Not Because Im The Great Lakes Dealer. All The Bugs Have Been Worked Out. Remember Max & The Rest Of The Drive People Use Bravo Parts & Design. It Will Not Hold Big Hp & Torque. Give Me A Call If You Need Any Info. Ron Bender 216-390-1330

two local guys have had good luck with the Bmax, the first boat is a 36 spectre with 500efi's and whipples, he popped a couple xr bravos and made the switch to bmax , no problems now. The other guy has a 35 motion with custom 1000 hp motors and runs bmaxs with excellent results

Hey TAZ I know a dude that may need a set of B-Max's what kind of money is he looking at?

12,206 Each.