I haven't tried them, but a hardcore simulator buddy of mine has a pair and he did not like them at all. And he and I usually have the same taste in these things..
From what I gathered from the 'review' he gave me, you'd be better off with a TrackIR device to add to your sim rig, if you havent got that allready, Terry. That does more for the immersion than a pair of those glasses, so my mate also said. His TIR is always on, and the glasses are in the attic, in the box of old pc equipment, so to speak. So that means a lot to me...
But hey, perhaps you like them, it's personal I guess.
Fred