Hmmm. The Zenithink Upgrade models use AML8726-M3 chip. Seems Amlogic changed these chips to work @ lower voltage. The M1 were 7.4V. The M3 appear to be 3.7V. Must now support mobile RAM instead of standard RAM chips. ie, lower voltage RAM chips.Be careful, the new Z102 upgrade use 5V charger now. not 9V like before.
I did not checked and I charged my new unit with my old Z102 charger, realizing after that they have different voltage...
That means the 8726-MX could be 3.7V too which would be very good for battery life. Will know for sure once tablets get released with this chip. Then can check plug adapter to see if battery is running 3.7 or 7.4V.
I did quick search to verify that this info is right. Ramos W6HD uses 8726-M3 chip too.
http://www.amazon.co.uk/Android-tablet-replacement-supply-adaptor/dp/B007FI05DW
http://www.pandawill.com/ramos-w6hd-tablet-pc-android-40-7-inch-hd-screen-cortex-a9-8gb-hdmi-dual-camera-p55876.html (notice battery is 3.7V)
Battery life should be better with the Upgrade models. Do you notice this? Or is it the same?