I purchased the extended brake lever for my GT...after installing and riding 70 miles with it I noticed that the brake light was constantly ON...this is an issue with next generation engine braking...you will slow MUCH faster and it is wise to give the brakes a couple of taps to let your buddies know you are slowing up...ESPECIALLY in the twisties...
Took it to MM Powersports(Yamaha dealer in Hancock, MI) Chad and I could not adjust it so the brake light would turn off...
Replaced with a standard lever and all was fine...
Judging after 125 miles, I do not believe it was necessary to have the extended lever anyway because the riding position when you corner really does not necessitate "hanging out" laterally...instead it is more of a forward lean like the Rev...
My $.02