Doug, as noted above I'm using the line level inputs with mine, if only because my SET amps complain mightily if I try to use the speaker inputs. I ran some frequency response tests yesterday with the sub amp both on and off and really don't believe the results but for what it's worth the Gallos on the Mapleshade stands were remarkably flat down to 20 Hz (with sub amp) and 31.5 Hz (without sub amp). This was with the Rives/Mapleshade CD test disc available from Rives Audio, in conjunction with the Radio Shack Sound Level Meter. Test signals on the Rives disc are supposedly adjusted for the inaccuracies of the Rat Shack meter. But as I said, I really question the low-end results. Not even Gallo claims this kind of response.
As to the question of other dedicated stands, Bright Star sold some for a while and Stein Audio still does (I think), but in Bob's and my comparison, the Stein stands didn't do much better than the stock setup. Dave