Bests & Worsts Reviews from Amazon

I've had a Kindle Fire (5th Generation) for several years and have been generally happy with it, so I expected the Kindle Fire 7 (9th Generation) to perform at least as well, especially for 4X the internal storage (32GB). I was wrong: the Fire 7 runs very slowly, frequently freezes, crashes out of apps, and doesn't appear to recognize the 64GB microSD card I use for storing books. It also does not "play well" with Amazon's own website and servers: most of my books are checked out through the public library, and even though the Fire 7 is designated the "default" device for downloading my books, the books are not downloading to the device, but are downloading to my old Fire. Thank heavens I kept my old Fire and traded in an extra Kindle for the Fire 7, as the Fire 7 is going back for replacement.