For the past 7 years, i've been using Samsung Galaxy Tablets (Tabs A, & E, models). I love them, but i need to get a new one, and Amazon has great payment plans on their devices.   I'm just curious- how different are the two? The model i'm looking at is the "Fire HD 10 Tablet with Alexa Hands-Free, 10.1", (1080p Full HD Display, 64 GB, Black). I hear i can download the google play store as an APK, & will be able to use apps from it once i do.  This is key, as i have mostly epub files (far, far too many to just convert). If i can install Aldiko or Moon+, i'll be good there, but are there any other major limitations of it, compared to a SGalaxy Tab? 

I'm looking at the one without special offers, so those wont be an issue.  I use kindle & prime, but only occassionally. 
Thanks!

Sure you can install Aldiko or Moon+ on the Fire HD Tabs. As the Fire HD Tabs essentially run on android with Amazon's skin. However the specs on the Fire HD tabs aren't very good, so if you are planning on using them for gaming then I would recommend on sticking with Samsung's Galaxy Tab range. Also if you are planning to use them for media consumption then you are much better of getting a TabS, as they have a much better display.