Chicago Cutlery can last pretty long if you take care of it, though the handles aren't great.
A lot of inexpensive knives can be made quite sharp. Even the basic white handled Dexter-Russell fillet knives work fine, you just have to take care of the edge. Stainless knives really shouldn't rust if they're made with decent steel.
A big advantage of nice knives isn't just the ability to get a great edge it's the overall performance. Much more comfortable in the hand especially when you're using them for a long time. If your knife skills suck you may not know the difference.
You're also more likely to take care of good cutlery. Don't cut on porcelain surfaces, keep them out of the dishwasher and never let them sit wet. Don't sharpen more than necessary and hit them with a steel before you use them.
And they look cool.
-spence
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