I sell digital equipment in another field of endevor.
Most electronic items will fail rather early, like the first day/week/month, or last forever.
So if there is a problem with a unit, it is usually going to be right out of the box.
Rebuilt units, for WELL ESTABLISHED models, can represent a good value, but in the field of audio equipment where only the brand is well established, and the model changes as fast as I change my undies, there can be a problem with rebuilt units. My belief is that many manufacturers are bring products to the market so quickly, there is no long term reliability record for specific models.
For a model that has been on the market for more than 1 year, and is not scheduled for replacement or upgrade by the manufacturer in the next year represent a good potential value in a rebuilt unit. A fresh on the market model should always be avoided in a rebuilt unit unless accompanied a very long term manufacturer warranty.
If an item doesnt have moving parts, such as a CD Transport, I dont suggest buying an extended warranty, unless it is free

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