3 reasons against buying the A version:
1. It has little to no support or information.
2. It costs more than the B version - basing only on Willgoo's prices, it now costs $20 more, and even that isn't the best prices you can get.
3. If you're going for Android games, most of which are optimized for touch screen controls, why not just buy a cheap phone or tablet with superior specs? You can probably connect it to a BT gaming controller, and you'll have a better experience overall.
Personally, I think the market is in the calm before the storm right now. nVidia silently debuted the new Tegra SoC, which brought 64 bit processing to android. We also haven't seen a new gaming tablet from the Chinese markets in over two months - the S5800 doesn't really count.
This means that in a short while we'll see new, better gaming tablets and we can expect the Shield 2 in the coming months.
So if I were you, I'd wait a bit. You might see extreme price drops on JXD's products, or maybe even fancy something else. Keep in mind that Tegra 4 already blows every other SoC out of the water - and the Tegra 5 should perform almost 3 times as fast.
