Sorry to be a pedant, but it's worth noting that the Santoku knife isn't the Japanese equivalent of a Chef's knife. That would be the Gyuto knife. These page explains the different blades / knives quite well: http://zknives.com/knives/kitchen/misc/usetype/all/index.shtml

Apparently Santoku knives are actually a western influenced design, and not that traditional.

Hey not sure if I'm too late, and the purchase has already been made. But for what it's worth, I've used Santoku knives in the past, I still own a couple of they're nice knives, however I tend to find myself using Global's version of a Nakiri/Santoku far more often than the more traditional wide blade Santokus. I've used various cheaper knives and always struggled to keep a decent edge on them, then I bought a couple of Global's and the rest is history. Never used Wusthoff, but I believe they're just as good as the Global's. Robert Welch knives are also very, very good and considerably cheaper than the more prestigious brand name offerings.

This is the knife I'm talking about, it seems to be much closer to a Nakiri, than a Santoku in my opinion: http://www.globalknives.uk.com/range/gs-series-chefs-knives/gs-5-global-14cm-vegetable-cleaver

Also, this seems very, very similar but currently at half the price: http://www.steamer.co.uk/chopping_preparing/knives_scissors/chefs_knives/global_michel_roux_jr_usuba_knife.htm It's now also being called an Usuba, which from what I understand means it's almost identical to the above, but sharpened only on one side of the blade. I've never used it, so can't comment other than that.

Between that, my chef's knife and my smaller utility knife I'm pretty much done. The only other knife I use (very rarely) is my Chinese cleaver, and that's usually for delimbing / decapitating something.