I think kit suppliers are in an especially exposed situation. They have to choose what their policy will be in regards to things like this. Do they attempt to fix it? Do they replace the kit? Or do they have some fine print somewhere that makes it clear whose responsibility it actually is? Then, you have companies like Elecraft that say they "...won't let you fail...". I'm sure even they have some limits.
I hate to admit it, but even with my experience, I've had a kit or two that never worked the way I expected it to, and I've also had kits that were incomplete or had the wrong parts. Usually, the vendor has been of assistance, but I don't really expect that much help - if I mess it up, it's my problem.
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