Guys, Thanks for the information. I like the AR Engineering unit as well and I know It is high quality. Even for a moment I was considering a Milodon gear drive unit too but in the end, I only need vacuum seal and I don't see Myself unzipping all the stuff in front of the 'adjustable' cam setting window for a few less milliseconds of ET. Poor track prep can steal more than 'optimal' cam setting gain in My eyes. For now, I can't justify the cost of the upscale timing covers. Yes, they offer more utility. Wheels Up!