Helllll no.
All it takes is one vulnerability in the device or app and anyone can now get into your house.
Also 2 years from now when Amazon stops supporting older models and stops providing updates...you are now stuck with a useless lock and are forced to upgrade.
Most of the smart home devices are nothing but programmable logic controllers (PLC's) which have virtually no security built into them. These devices have been around since the 50's and with the internet of things (IoT) have opened up whole new doors in security vulnerabilities.
There are ways to tighten up the security such as airgapping them from your internal wireless network and preventing them from internet access (which pretty much defeats the IoT purpose).
I was at a cyber security task force meeting a few months back where the IT director of Chamberlain garage doors was a panelist and I honestly felt bad for the guy as he was getting hammered in regards to security of his companies products.
What's even scarier is that most of the US's infrastructure (power plants, street lights etc) run off these same PLC's which is why you hear so much in the news of China and Russia hacking our grid (they successfully have many times).
To not totally get off topic there is no way in hell I would let anyone from a delivery company inside my house/garage. I would rather have a waterproof box on the stoop of my doorstep and then use the same example of providing amazon a key or code.