Isn't Lenovo the company that made, and currently makes, the (previously IBM-marketed) Think Pad? I know those were always very well regarded. I'd certainly give a tablet of theirs a try, if my assumption is accurate.
One and the same. The build quality is good on the A1. No magnesium like the Thinkpads, but still good.
If you prefer the walled garden approach to tech, the Fire is the better bet.
The Lenovo can shop the regular Google Market, plus the Lenovo store and the Amazon Market.