Here is my list of guys with better "stuff" than Burnett. I do include control... as control is a very important component of stuff. More times than not, if you cannot get great "stuff" over the plate consistently, hitters will pick up the rotation of the ball and just let it go.
Here is my list. (INPO....not sure if there is an official internet-speak word for "In no particular order", but if there isn't, there should be;)
Peavy
Rich Harden
John Smoltz
Sabbathia
Josh Beckett
Felix Hernandez
Zach Grienke
Roy Halladay
Johan Santana
Chris Carpenter
Tim Lincecum
Brandon Webb
Erik Bedard (when healthy)
Cole Hamels
Carlos Zambrano
Roy Oswalt
Edinson Volquez
Possibly Scott Kazmir
Definitely Matt Garza
Dan Haren
Jon Lester
I also think some would argue Dice-K though Burnett has displayed better control.