I put on on a Strat in the 80's when they first came out. Dumbest thing I have ever done to a guitar. I absolutely killed the tone. Yes it stayed in tune, but it was completely dead and lifeless.
David Gilmour did the same thing and found the same thing I did. He quickly ripped it off and wanted the stock trem back. Only problem was that you had to rout the guitar to put the Kahler on. So he had to have a piece of wood cut to fit the hole. And there you have his famous black Strat.
I have not tried one since, so they might not be as bad as they were, but it completed ruin a good Strat then. Many of the Strat players on the circuit at the time did the same thing. I only met one guy who actually liked it. But he had a wall of effects, so you couldn't really tell as much on his sound.