not sure how many times this has been discussed, but lets talk about drivetrain loss on a AWD. How much drivetrain loss are we expecting on the AWD? I've heard only a little and wont make a significiant difference, but some people also say that AWD drivetrain loss will definitely be noticeable.

and if you have time, let's compare AWD with RWD

It's roughly 25% loss. Yes it is noticeable at highway speeds. Say I run mid 13s, and say a supra or a TA run mid 13s. I will jump out early due to the launch, they will gain the distance lost in the 2nd 1/8th. We can run the exact same times (them with the higher trap speed) and then if we were to continue they would continue to pull away from me.

People do over-rate it IMO, just like many other factors, when they put too much weight on just 1 part of a race. It's just like anything else, gearing, aerodymanics, driver ability, and of course powerbands. Every part plays a role in a race, and you have to look at the whole picture.