Hi 57chevy,
Post #2 here has some thoughts about the various types of slow response latex that several manufacturers are making including Talalay GL slow response.
Post #6 here has some general feedback from people I know or have talked with who have tried it.
A forum search on Talalay GL slow response (you can just click this) will bring up more forum posts that mention it.
Perhaps most of all you could call Ken at mattresses.net who is probably has the most direct experience with it of the people i know and could tell you more of his impressions and the feedback from his customers as well.
Phoenix