I've found that 95% of the time, a few lightweight pieces like pucks and cut gears don't help you finish better in the main if you have a quality rig already. That 5% exception is when there's a jump section that you can clear just because of that extra "pop" you get from the added acceleration. Tracks should be designed to avoid those scenarios, but it does happen and then everyone thinks you need all the hot parts to be competitive.