I've said this before, and Jeff has disagreed, but at 40X magnification I see scratches left on the bevel by the SG that do not get removed by the honing wheel. What I see at that magnification is that the surface between the scratches gets polished, but the scratches remain.
I'm inclined to agree with you Herman, while I don't have a Tormek machine, my current setup utilises a 1000 grit water stone and Tormek compound. I find that I have to use a fresh amount of the paste each time if I want to remove the scratches, which takes a bit of time and can be messy so I add a little and often. Even without a magnifier I can still see the old compound only polishes the scratches, more importantly it doesn't give a clean cut on my carving chisels.
So currently I have an intermediate step where I hone with some green wax from another sharpening system and this gives myself better, faster results then finish off with the Tormek compound. I see the Tormek honing paste a bit like their stone, it's a dual grit medium. Starting off at 3 microns (about 4000 grit I guess) but breaking down to 1 micro as I understand.
Therefore I would be interested in a specific honing wheel with single grit size, it's just the price makes me consider other options.