Hi Bob:

How about using this as the Greg. Secondary for a larger scope. It would depend on what the curve is but that is the question here anyway.
If Anthony uses this for the Primary then his secondary really will have an even steeper curve. Perforating a finished mirror also has the danger of introducing stress.
Of course I know you know all this but for a first project this may be a bite bigger than Anthony would want to chew. I would recommend experimenting around, maybe use awhile
as a lensless Schmidt camera or try and trade. Other uses may include a component in a spectrograph or collimator etc. Just a thought anyway.

Cheers,
-Rick