test tools needed and how stiff?

I have ordered the new acme screw from McMaster and Moglice to redo my slopy
nuts. I have more or less decided to get a Taig spindle to use on my setup.
I want to get started on the base, part of me says a couple layers of
OSboard glued together will be fine, another part says idiot, you gotta use
like 3/4 inch plate steel. I would like some feed back on this and would
using 2" black pipe to make an upside down U over the 6x12 Enco table be
good enough? I was thinking of filling it with concret or something.

I guess my problem is I can't really decide if its going to be a mill or
router. The project started to be able to prototype PC boards, but it sure
will be nice to make some metal parts. As I see it a mill will do both, a
router won't.


Another topic I am pondering is what tools I will need while setting all
this up.
A $10 test indicator and a $15 0-6 inch dial caliper cut it? What's the real
difference to the user in a $150 indicator and a $10 one?