I cannot comment on the Keisler, but I have driven 5 cars with the Passon and love it! Jamie is indeed a great guy with customer service second to none. The cars I have driven with his trans are a 68 Dart 5.7 Hemi, 2-68 Hemi Darts, one with 720 rear wheel horsepower, a 71 Cuda with a 6.1 Hemi, and a 71 Challenger with a 6.1 Hemi. I have driven plenty of cars with TKO's and enjoy the way they work though. It really depends alot on your skill level also, the Passon is truely a bolt-in if you already have a 4-speed, and uses all factory components if you don't.