CPC or GPS?

Does anyone know the pactical differences in these scopes, aside from price?

I'm concerned about the plastics of the CPC mostly. They don't look as
robust to me as those on the GPS models. Also, what about the new Meade LX90
series in 10" and 12" apertures? Are these more robust or less robust than
the Celestron 9.25 and 11?. While optics are obviously important, it is also
important that the mechanics of the mount be robust and long-lived.

I'm considering the purchase of a GoTo SCT for binoviewing (as I've
indicated elsewhere), and while 8" would be ideal for portability reasons,
10" or greater would better suit my skies, as well as help make up for any
loss of light in the binoviewer.

-Stephen