I use Zwilling J.A. Henckels. Not the most expensive, but I love these knives! I tend to pull them a couple of times over a sharepning steel each time before usage and then ask my father to sharpen them every once in a while. (An elaborate opereation - his greatest hobby is renovating old furniture, so he's a fan of most things sharp.)
Incidentally the best knife I've ever used in a kitchen belongs to him. It is a curved handmade knife of unknown origin (likely Finnish) that looks pretty much like a scimitar and is the size of a small short sword. Sharp like no other knife I've tried and heavy.