I was wondering why there were a bunch of membership requests in the Yahoo group when I got back from the airport...and then I saw this thread -
Welcome aboard Cleve!
I could probably write a lot more than anyone would want to read on how I am enjoying my GRT EFIS, but go look through the Yahoo archives and you'll find tons of info from folks that are flying it.
I'll just say here that I have over 200 hours on the Valkyrie with the Dual GRT EFIS, and have yet to have a single lockup, glitch, or hardware failure. The system has done exactly what it is advertised to do, and it has a tremendous potential for further expansion. I drive mine with a GNS 430, and link it to a Pictorial Pilot ad Altrak from Tru Trak - all play together extremely well. The GRT is a true EFIS - with an emphasis on the "S" for "System". It really puts all of the necessary information in front of you, and makes flying with an autopilot in IFR a breeze.
There are other good systems out there, and I suspect many more advancements in the future from all the manufacturers, but I think you will be pleased with it here and now.
Paul