I'm going to pull the trigger and do the transgo shift kit, sonnax shift overlap kit, and the amg blue top solenoids on my 99 E300. Now that the weather is warming up again, I'm hoping to do it sometime in the next couple of weeks. From my research, the transgo kit isn't made to improve or increase performance on the 722.6, but to remedy worn parts. Same goes for the Sonnax kits, I'm doing both for preventative maintenance and the AMG Blue Tops for the performance. Why? I want to do the most supporting mods before upgrading the turbo and injection pump.