That decal look is essentially what the fingernail polish did.
My Helvetica $18 DealExtreme Scissor will probably outlast a uncoated Leopold key but not as long as the HHKB. That is good since the HHKB costs $275 it should.
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(http://farm6.static.flickr.com/5004/5296946063_ac01715350_z.jpg)
In my experience, both yes and no, it will probably last as good as the fingernail, but I have a similar keyboard, and although the lettering won't get worn and banish with us, it will get eventually dirty and turn into a less shinny color, more like brown. This fingernail polish I'm talking about is so 'thick' if the term is valid, that no matter how dirty and sweaty hands you have, the lettering won't get brown, BUT it is way more 'shinier' than your picture. To image how shinny it gets, try to think of a keycap covered in some body oil, the one that you seen on those boobs in that porn clip, but it gets really hard.