Unquestionably, the best "bang for the buck" is the Amazon Fire HD 10. You can not beat the price. The screen is very nice and bright. It does have a few negatives.
- No cell phone connection (but that may not be an issue for many people)
- No GPS so no mapping software
- Probably the biggest negative is no direct access to the Google Play Store and it thousands of apps.
There are
work arounds to allow you to load the Google Play app, so that is not a complete bust.
EDIT : TetherGPS allows you to share GPS information over WiFi from one device
(say an Android cell phone with GPS) to another device
(Fire tablet).