My father, who passed away recently had one for his Kubota. It is a Harley Power rake T-6. Be prepared, they are expensive. I do believe he paid almost $6000 for it by the time he got the valves installed on the Kubota. He swore by that thing. He said it basically replaced three other implements and he could completely prep ground for seed with it in one pass. It's for sale if you are interested...
From what he said, I'd recommend one if your in a business that would require seedbed prep.