Kees
I have just rerad Derek´s test of some chisels, a year ago. He tested several PM steels and some old fashioned carbon steel ones. The strong point of his test is how he tested the amount of wear. Instead of looking at micro photographs, which don´t really tell you much, he tested the sharpness through paring end grain pine. That´s a real sharpness test, just like how Kawai-Kato test sharpness with force transducers in their planing machine. Dereks test is a lot cheaper of coarse!

His conclusion was that the PM chisels where a bear to sharpen and needed diamonds. On the chopping test they really didn´t outclass the Japanese chisel, which was easy to sharpen to a very sharp edge and kept on to that edge for a very long time.

I have similar experience with chopping a lot of dovetails in Jatoba. My older Berg chisels needed to be resharpened after every pin, the Koyamaichi's easilly hold up for a drawerside. I polished the edges after each side just to prevent catastrophic failure of the edge, but they sure were still reasonably sharp.

There is another test on Dereks page about the paring/planing ability of these steels. The Japanese one again took a very sharp edge early on on the test, but didn´t hold it quite as long as the others.

In other words, the Japanese really manage to create some very good chisels with simple tool steels. They are easy to sharpen, get freakingly sharp and hold an edge for a long time. The ability of PM steels to hold an edge for longer time seems especially aparent in a paring/planig situation, not so much when chopping.

The new PM V11 stuff from LV looks promissing. If it really lives up to the testdata from LV in their sales brochure on the web, it´s going to be a succes. I agree with Bill that the planing data with MDF and almost zero clearance angle looks a bit suspicious. I am very curious how this stuff will hold up in real life. I´ve never liked the idea of the PM steels, because they seemingly need a new sharpening regime with diamonds. So now LV comes with a PM steel that's reasonably easy to sharpen, they might have a winner.