Based on a test kitchen Japanese Slim Vs. the German Heavyweights by Denise Landis of nytimes.com, she posted that:

" Now, many chefs are starting to switch to a new style of knife, from Japan, that is lighter and more flexible than European knives. These sleek knives from Yoshikin, called Global, represent a revolution in both material and design."

She concluded her test by saying that:

"Taste in knives is, of course, personal. And cutting is not the only issue. Any good knife will require care to remain sharp and durable.

In the end, as much as I wanted to think of the Global knives as the Excaliburs of the kitchen, I realized that no one knife fits all. This new blade works best for slicing, but for chopping, I'm keeping my trusty Wüsthof."

If you ask me, there is not a lot of difference. I have used a lot of good German knives, and living in Japan I have tried some good Japanese ones.

At the moment I use a Tojiro, but had a great knife from a boutique Japanese knife maker that was absolutely superb and which I ended up giving to my mother-in-law.

The biggest difference is the attention to detail. Most German knives have a really generic, manufactured look. My Tojiro does too, but if you spend the money and get something from a specialty knife maker, you get something that is more a work of art.

Some Japanese knife makers employ similar techniques to those that are used to make Japanese swords. They use carbon steel, they sharpen easily, cut precisely and look like a million dollars.

On that basis, I would pick a Japanese knife, but understand that I live in Japan and that they are a lot cheaper to buy over here than in other countries. Performance-wise, I doubt you will see too much difference, Germany makes some great chef's knives.