i've used both the shee master and gsxr, i found the bolt pattern of the gsxr master to be more "inline" to hug the frame tighter than the shee "offset" mounting holes.
allowing a shorter extension on the brake pedal, more like the stock 03+ and shee pedals.
the gsxr also allows me to make a "less complicated" bracket
pics...........
gsxr:
banshee (style):
i use the stock 88-02 brake peg and pedal with extension welded on, then slightly bent in right past the frame, to align perfectly with the master, the clevis/rod of the master will spin to match the angled extension.
here's a better pic of a pedal with extension, i start with 4-1/2" welded on, but end up cutting off about 1-1/2" when finished mounting the master to it.
in the jig i made with spent .357 shells to get them close to the same 10-15 degree downward angle for every set

if it isn't angled down, the master will need to move up the frame further as the rod can't be cut that short, and it helps push the rod up in straight.
this is an old pic i took for someone, explaining how i do the extensions