More sold does not mean it's better - far from it!
I have had a chance to experience the galaxy note 10.1 2014 and the new galaxy pro 8.4 for about 1 full week. This is because one of my family member's husband works for you know who, Samsuck. I also own a note 3 and having it rooted, I'd never buy another iPhone with iOS 7 again.
Anyway, there is no way in hell I would buy a galaxy tab or any android tablet over an ipad. #1 reason are the apps - there are just too many quality rich multimedia apps on the ipad and optimized for the ipad, no android tablet comes close.
#2 reason is the fact that compared to my ipad AIR, side by side, the web browsing on iOS 7.1B5 is just faster than any of my qualcomm quad core devices tested on. Android phones are just awesome - but tablets are another story. Dual core A7 with apple's own IOS just so good it really makes having quad core silly; especially when software doesn't even really use up the quad core performance so even having so much specs really isn't 'that great.
#3 reason is the quality of the device - the screens on the note 8.4 and note 10.1 2014 is just spectacular but it's also a "meh" comparison to an ipad retina. At the normal distances, it's a moot point.
#4 The battery life on the air is just phenomenal. The note 8.4 doesn't last more than 7-8 hours, pushing 9 hours tops if I have everything at minimum (backlight, etc)
The best part about these samsung tablets are the fact the 10.1 2014 uses usb 3.0 for faster charging, both allow microSD memory cards and the cameras are really great. They also have flash on back. The software is android and of course there are a bunch of great android phone apps but the tablet app space is just pathetic.
One big thing about apple's ipad is the fact if you have kids, it's just the best device because not only are there a ton of apps for them to learn and play with, there is the "guided access" mode on iOS in which I can lock and prevent kids from messing with things. The restrictions are also fantastic on an ipad and you can prevent deletion of apps, etc. With the android, there isn't anything like this in sight. Rooting is one thing but out of the box, the ipad is just superior.
On paper, these tablets blow the iPad Air out of the water with specs alone but seriously using them extensively, you will see the iPad Air is just substantially better. I would never recommend an android tablet regardless of pricing over an iPad Air.
Edit: There is one thing that I wished iOS 8 will have. That is the power to multitask a messaging app or web browsing app Because I reallly like how my note 3 can float an app on top of any full screen app running. I don't expect to multitask like on my laptop, but being able to message while surfing the web or a video is just great on an android device (samsung that is).