"While I agree with most of your points on hot water.. will it really?
I mean since it's not heating it nearly as hot could it actually get it

"hot" quicker as there isn't as much overhead? "

The issue isn't how fast it gets hot. The issue is how much heat there
is there to begin with. If you have the water heater set at 140, then
you have 40 gallons of 140 degree water, which has significantly more
heat than say 110 degree water. When taking a shower, you will have
use more of the 110 degree water, so the already heated supply in the
water heater will be gone faster. And as for how fast it heats, the
water heater only can heat water at a certain rate while the unit is
on, no matter what the temp is set to.