Didn't know about this Kindle Fire HDX before, thanks for the tip! Is has 2x the CPU power these A7 iPads have, and a better resolution than Retina, and a 8MP camera as well. And it's lighter on the wallet than iPad Air / iPad Mini Retina.
LOL, gonna pick one Fire HDX up really soon!
Have fun with your Fire HDX, but you should maybe check out the facts - not sure where you got yours.
iPad Mini - 64bit dual-core A7
Fire HDX - quad-core snapdragon (quad cores, but less performance) http://gigaom.com/2013/09/19/tests-show-iphone-5s-a7-chip-is-dual-core-still-beats-quad-core-android-competitors/
iPad Mini - Resolution - 2048 x 1536 (324 pixels per inch)
Fire HDX - Resolution - 1920 x 1200 (323 pixels per inch)
iPad Mini - Camera - 5MP rear-facing / 1.2MP front-facing
Fire HDX - Camera - NO rear-facing camera / 1.2MP front-facing
Not that specs are generally any indicator of performance, as Apple has proven over, and over, and over again.