tmr are really good folks, they are earnest they are conscientious, but no one is perfect and gets everything just right every time, all the time
agree with elliot, serial # does not speak to age of unit w.r.t. warranty, which is triggered by the actual sale date to a customer from a retail establishment, and as elliott says, therefore the original retail sales invoice is the key piece of info that manufacturers (or their importers) want to see when a warranty claim is sought by an end user ... furthermore, specific manufacturers clearly state terms for their warranty transferability or applicability, and conditions pertaining to it (e.g. you need to register the product on their website etc etc)