Re: Going for a David Sanborn sound...
Yea...basically what Yani said...plus a record contract as well.
Seriously, my thoughts are that no one can get a "so and so" sound. You can try, and you might get close, but you're NOT David Sanborn, I'm not David Sanborn, our physical makeup (like muscles in the cheeks and jaws and etc) is not that of his. So even if we get the Mark VI, the metal Dukoff 6, the Vandoren 2&1/2's, and a Harrisson Ligiature (which I have yet to find, thank you) we will only get close to the sound he has. Even then if ya don't have enough chops (I don't know if you do or don't, I'm just saying) you won't even get close.
But as I listed above; if you want to try; Mark VI, Bobby Dukoff 6, Vandoren 2&1/2's and a Harrisson Ligiature (not Joel Harrisson). I found this out on david-sanborn.com You'll have to look at the link for equipment and you'll see it for yourself. He even soaks his reeds, so that's another point.
Maybe you'll take my thoughts into consideration, maybe not. Either way, I wish you the best of luck!