I prefer an analog gauge, graduated to .0001. That way, I can see it sweep towards zero, and very easily take a reading off the needle, without having to digest a bunch of moving numbers. IMHO, .0001 is essential, .0005 is too vague.

[img]http://i.imgur.com/boeexFms.jpg[/img]
31 Plymouth Coupe, 392 Hemi, T56 magnum
RS23J71
RS27J77
RP23J71
RO23J71
WM21J8A
I don't regret the things I've done. I only regret the things I didn't do.
"Wise men talk because they have something to say; fools because they have to say something. ~ Plato"