I own a Nexus 7 (2012 version) and I was pretty satisifed with it. It is small and I used it primarly with Zite / Flipboard and to quickly read my news feed. The device is nice, but it has crappy hardware and, after a couple of years, it stopped charging.
It turns out that there is a problem on the USB port that prevents proper charging. The simplest solution is buying a Docking Station, but Asus decided to stop producing it, and now you can only find it on the internet at a really high price.
The cheapest solution is buying a Flex Charger Cable and replace it by yourself. After replacing it the tablet started to charge correctly.
Then I noticed that even after a full reset it was slower than in the past, so I decided to check if it is a problem in the Lollipop upgrade. Google has a public page where you can find all the stock roms for Nexus 7, so I downloaded the Android SDK, downloaded kitkat 4.4.4 then restored the device to KitKat in almost less than half an hour.
Now my tablet is back to life. It doesn't have astonishing speed, but it is perfectly usable as it was in the past. I’m also happy because I was able to avoid wasting a device that can still be useful.
In the end there are a couple of compliants I have about the Nexus 7.
If the device has a known problem with USB charging (lots of users claim to have this problem) Asus should have continued to produce the docking station instead of forcing people to open and fix the device.
Lollipop is really slow on Nexus 7, and Google should do better testing of new roms against official old devices and warn the user that upgrading to the latest version can impact performance. Also, I’d like a simple option to being able to rollback to previous Android version directly on my device, even if it will reset to factory settings.