Found Collection

I'm moving to all-grain and am seeking a stainless
steel pot 30-40qt and I have some questions:

Anybody have any experience with the 7.5 gal pot
advertised in Zymurgy gadget special issue for
about $70?

Is 7.5 gal big enough for 5 gallons in the primary?
How much evaporates in a full (1.5 hour?) boil.

How do you define a quality pot -thickness, construction?
Are they all good enough?

Any insights would be appreciated,

Roy