It seems after seeing Ettore's footage that sharpness he is getting it undeniably one of the best. Since his setup is generally like the DOF machine tutorial, it must be either -
1) The achromat
2) PCX lens
3) The correct distance from the DV camera

Which of the three is the magic bullet, I can't figure out - but I haven't seen that quality and sharpness yet in any adapter...
Personally I don't think it is the GG because of all the testing on different diffusers / sandpaper / microwax tests that have been done here.

Any ideas?

No magic bullet. - Care in selection of and fitting up of all those components.

Bob is right. And if you build it sufficiently long, no PCX is needed.

And if you build it sufficiently long, no PCX is needed. ... which is best choice in my eyes, because of possibility to avoid lots of side effects.

... which is best choice in my eyes, because of possibility to avoid lots of side effects.

Exactly :) The less glass, the better.

Ettore's footage is excellent. However keep in mind three things:

He's using a PAL camera, meaning better res than NTSC SD. I've been continually impressed by how much better PAL SD stuff looks than our NTSC equiv.

The clips are half size.

They are 4:3. Shooting 16:9 uses the same number of pixels..but stretched.

Good point Dennis. I did notice that myself and just wondered if he was cropping to make the images a smaller size for the internet.