Followup:

Returned the 'Silver' coated Avanti blade and ordered a 50T Frued
Diablo. Probably not as good as a WWII but half the price. I am also
very happy with the 80T Diablo I have, cuts great and will easily rip
3/4" Maple even though it is not made to do so.

Checked the runout on my arbor, barely perceptible ~0.00015. Good.

Checked the runout on the flange and at first it was ~0.0015! Then I
noticed that even touching the belt caused the needle to jump
(contractor saw). So I took the belt off and the flange runout is
~0.0003 after a little touch up with emery cloth, good enough for me.

Put the original 28T Jet blade on that made maybe three cuts in its
life and the blade runout was 0.005! WTF? Spun it 180 and now the
runout was 0.001. Spun it back and runout was 0.002? Took the blade
off to see that it was scratched/smutzed up. Emery clothed it and now
the runout is around 0.001 in any position (without the belt). I'm
satisfied the saw is OK and the Avanti blade was a POS.

OK, so is all this checking worth it? I think it is, it takes maybe
five minutes to check the runout of a newly mounted blade. Well worth
it to find out that an errant wood chip got stuck between the blade
and the flange making a smooth cut nearly impossible. I plan to keep
the dial indicator in a much handier spot. That way I can check a
blade that has been lying around for a year with an Allen wrech under
one side and a stacked dado set sitting on top of it ;-).

Enough measuring, I need sleep so I can make some sawdust tomorrow.