I'm doing a conversion from hydraulic to manual timing belt tensioning on my 1.8T 20V 06A. There seem to be two main types of manual tensioners that I can use and I was hoping for feedback on which is the least likely to fail in a car that is a daily but competes in hillclimbs and does track days every month.

1. 2.0L 16V ABF internally sprung automatic tensioning.
Which manual tensioner best for 1.8T 20V-img_6370-jpg

2. 1.8L 16V KR fixed tensioning.
Which manual tensioner best for 1.8T 20V-kr-1-jpg

From what I've read, the older KR style is very reliable but the con is that as a fixed tension that it can wear out the bearing quicker (not sure I care about that as I'd be doing my belts at half intervals anyway) and initial tensioning cant account for belt stretch over time.
The ABF being internally sprung is apparently more reliable than the hydraulic tensioned tensioner that is stock on my BJX but is it as rock solid as the KR? Apparently its automatic tensioning runs the belt looser when stopped/at start up which then tightens up at running speeds. This is to prolong bearing life and account for belt stretch? but with the extra moving parts, are they as track reliable as the KR style?

so what I've mentioned above is what I've read which of course can be a bunch of bollocks so I was hoping to hear from experienced shops/individuals that track cars and know what lasts.

thanks
sam