I've recently been experimenting with Android devices, to see how useful they are and how well they synchronise with iOS and Macs. I've written a review of the Galaxy Tab 3 8" model, which I think is an excellent device: see http://www.amazon.co.uk/review/RODWFJOILTWVX/ref=cm_cr_pr_perm?ie=UTF8&ASIN=B00EC9C2E2&linkCode=&nodeID=&tag=.
I think the Mega is an even more useful device (as a Tablet....this is how I mainly use it), though is 2x the price. Here is my review of the Mega compared to the 8" Tab 3:
1) When using it single-handedly (e.g. when typing a short email/message and casual browsing), it is a better fit in the hand and weighs a lot less. Therefore, fatigue is much less of an issue when handling it.
2) It seems a lot faster in normal usage. The CPU isn't much quicker but transitions are smoother and Chrome loads webpages a LOT more quickly.
3) I can use it as phone (without a headset, of course), if I want. I use mine with a data SIM, and make&receive calls over VoIP. This even works over 3G. I have my deskphone number (Sipgate) loaded onto the Mega via the native phone app (which can be configured for VoIP calls), and it feels like using a normal mobile phone. When out and about without my regular mobile phone, I can use call forwarding from my mobile to the Mega, so when people call my mobile they are routed to my Mega's phone app. Cool.
4) Battery life seems not quite as good. With intense use it lasts from about 8AM to 5PM. This is with Zoiper and GPS running constantly. Have bought a spare battery and will see how battery life is without GPS always running.
5) For writing documents and long emails I have paired it with a nice Bluetooth keyboard (Perixx PERIBOARD-804i UK, Wireless Bluetooth Keyboard - Silver/White - 261x129x9mm Portable Size - Compatible with iPhone - iPad - iPad Mini - Nexus - Galaxy Tab - S3 - Note - UK Layout (Big Enter)
). Works just fine this way. It is held up with a Griffin DS Arrowhead Stand. To be honest, this is no different to using an 8" tablet (which is already too small to write long documents on...the virtual keyboard on any 8" tablet or phablet like the Mega is simply too small).
6) Its slim design means that it fits in my jacket or inner suit pocket, and is light enough to carry it this way. No need then to carry a bag/briefcase just for this device.
7) The UI design, especially the virtual keyboard and Settings app, is nicer than on the Tab 3.0. I don't use the Google keyboard with the Mega (like I did on the Tab) because the Samsung keyboard is good enough (unlike on the Tab).
Finally, about the experience of transferring from one Android device to another (in my case from Tab 3.0 to Mega), all the apps are transferred across automatically but the apps and pages are not laid out in the original way. This means a fair bit of time has to be spent laying out the apps and pages as desired. Also, none of the email accounts within 3rd party apps (e.g. the excellent K-9) are transferred, which means they have to be set up from scratch again. This all takes time and is not as efficient or effective as transferring between iOS devices.
I really like the Mega. It gets a lot of interest from bemused onlookers and friends but it is a very capable and useful device.