Actually that is why I am asking for advice...the benefits seem to be marginal.

$226 (refigure) + $104 (recoating) is at least $330 (still using the old diagonal, focuser, spider, mirror mount and tube/base)

...versus $500 (new scope)

A difference of $170...or 33% more and you have a NEW scope.

To put a more positive spin on the problem, OWL currently has a 40% discount on their coatings...so in this case that means $40 less.

So now it is $210 or 42%.

Of course I am ignoring handling and shipping costs which would affect the final solution.

And I am assuming that the Coulter mirror will need refiguring because of their generally poor reputation.

So even after getting a scope for "free", one has to wonder if it is worth spending the money and effort to upgrade an old scope.