Under what conditions would one want/need a cooler than stock thermostat or a
fan switch for the radiator. Are these for desert conditions? Are these for
areas with steep mountain grades? I'm relocating to LA are these necessary
for heavy traffic conditions in summer heat? The options follow:

I see Bus Depot among others offers two thermostats: a stock unit that opens
at 87 degrees and a cooler thermostat that opens at 80 degrees.
Part number: 025 121 113F and 025 121 113E respectively

Also in the radiator fan switch there is the stock switch and a "cooler"
switch that kicks in at 85 degees.
Part number 321 959 481D and 321 959 481D8 respectively.

I am currently replacing my radiator as it's not cooling well especially on
climbs through the Rockies. I would change to "cooler" thermostat and cooler
fan switch if necessary while I have the coolant system open. I will be
driving in LA but plan to hit the mountains whenever I can including Tahoe
and Colorado and Wyoming and the like.

TIA
Jeff
83.5 Westy
LA Bound