Steel or aluminum driveshafts?

So, if I'm reading all of this right.

Making the switch to an aluminum shaft is a good thing even
for a car that's just a street cruiser, not a racer?

Mine sees more time at the grocery store parking lot,
than even on the highway.
(Yeap, I pick-up the groceries, dry cleaning, all of those kind of errands in the SA 20--
it get's better mileage than our Mountaineer.)

Yes you are correct.

Thanks, I'll be adding a new drive shaft to the top
of my wish list.

It would make a great Christmas gift! You won't be disappointed!