Hello Melanie, and welcome to our Forum.
As a collector, I have learned one lesson well:
You never know the true condition of a piece until it is cleaned and restored. Many times the old seasoning and rust will hide condition issues.
(hairline cracks, pitting, scaling, etc.)
So I will bid higher on 'restored' pieces.
With that said, however, I also ask questions as to HOW a piece has been cleaned and restored. Doing it properly is as important to me, as not doing it at all.
Sand or bead blasting... big NO NO, use of power tools (grinding or wire wheeling)... big NO NO....
So... I'd rather see a piece cleaned and restored (but only if done properly!) :)