410 diff oils and sounds Q

[OneKiwi]

Two question here:

1.
Ok so my 410 is working well, im happy with it so far but I have been reading different set up sheets and Im a little stumped.

set up 1 has high grip carpet and driven on minispikes
15000F / 3000R diffs
1.5F/1.3R sway bars

Set up 2
similar track conditions and tires
5000F/7000R
no sway bars

Most of the other parts are the same or are real close, why so different?

Is this then down to driving styles and what they want/like?
Can you in the know see a big difference in how the 2 cars would handle?

2.
My other question is does anyone use grease/crc/556/wd40 on the drive train/dog bones/pins etc to keep the noise down and parts running smoothly?

I was looking at some Teflon spray or graphite powder, but will this help out or attract debris?

Thanks