What you said (if true) makes Apple a great business. And your reasonable arguments make a good case for that.
But does it make a good investment? A good investment is investing in a great business at a reasonable price. If the price is unreasonably high, then even a great business makes for a bad investment.
Can you post links here. I bought one in AliExpress and the readings were highly variable when there was no change in quality (as far as I can tell. Outdoor weather hasn't changed. I didn't cook, etc..)