I've had my Jackson Dinky XL since 1994, but I just recently installed a Tremsetter on my JT-580LP tremelo. It is by far the best mod I've ever done! I can now bend notes without the other strings going flat. I am also able to do a drop D tuning with the fine tuner on the low E string since the other strings still stay in tune when I tune down the E string to D. I've noticed an increase in sustain and volume as well.
The only minus I saw with the Tremsetter was getting used to the "clunk" when going up and down past the center position of the floating tremelo. The reason for the clunk is that there are two opposing springs in the Tremsetter: one for depressing the tremelo, and one for pulling up on the tremelo. To me, this was a small price to pay for the many advantages the Tremsetter provides.
The only minus I saw with the Tremsetter was getting used to the "clunk" when going up and down past the center position of the floating tremelo. The reason for the clunk is that there are two opposing springs in the Tremsetter: one for depressing the tremelo, and one for pulling up on the tremelo. To me, this was a small price to pay for the many advantages the Tremsetter provides.