Mark,
GS have always claimed their Optics to meet or exceed 1/12th wave, this is for the Primary Optic only. This was sprouted on their website some time ago and is still listed on their website.
http://www.gs-telescope.com/
(Click on Dobsonian)
Jim Sheng owner of GSO also commented on the Skyquest Telescopes Forum in 2003 in regard to this, in response to a post by Robert Bruce Thompson, author of the recently released publication "Astronomy Hacks"
http://groups.yahoo.com/group/skyque.../message/14046
I have not seen GS quote their optics as .94 strehl and I assume that feedback has come from Bintel or Andrews who have access to this test data either independently or from GSO.
It sounds about right as GSO quote a "minimum" 1/12th wave Peak to Valley surface accuracy which equates to a wavefront error of 1/6th wave at the wavefront which according to Bob Royces table is equivalent to a Strehl of .92. I have used a reasonable number of GSO mirrored scopes and all of the mirrors are very good with a couple being outstanding, particulalry so considering they are mass produced optics.
CS-John B