You welcome Colin.
In regards to System storage vs Usb storage:
System storage is just where Android is programmed to install applications by default, in a partition that can't be accessed by the end user without root access (and therefore doesn't need to be "shut down" when you turn on USB storage mode).
USB storage is where a lot of the data lives (cached files, music, downloads, documents,etc). But it's "off limits" to Android when USB is mounted on a computer.
In regards to JB for the ace 2
Here is the link for the official firmware updates by region:
http://samsung-updates.com/device/?id=GT-I8160
Note:
I don't know how familiar you are with the android system.
(You can download this firmware from the link and flash it on to your phone using Odin.)
But I suggest to you not to.
And just waiting for the OTA update instead.
That hopefully will arrive by the end of this month. ... fingers crossed...
Is useful to use the link to keep track of the updates.
And to download emergency firmware when you ruin the phone fir some reason...
So far the JB versions released were:
MB2- that was a leak beta full of bugs and only for testing.
MB4- was a more stable version that replaced the MB2 but still with Bugs reported.
Recently the official firmware was released by TMN Portugal.
MC8 -tailored for TMN Portugal.
And last week it was released in China the MC4. Not good for Europe.
The good ones for Europe so far were MB2/MB4/and the new MC8.
My phone is running JB MC8.
I love it...
But I had to root my phone to get rid of all the bloatware from TMN.
So far I reached the conclusion that
SAMSUNG ported the software from the Galaxy S3 Mini to the Ace 2.
This firmware is not fine tuned yet for our phones.
The firmware is designed for 1Gb chip. And we have only 800Mb chip.
Everybody is complaining about the lack of ram available and about the phone freezing.
SAMSUNG delayed the release because they are trying to find a solution for the problem.
As they need to downgrade the firmware to suit our phone.
Early days.
I hope this information was helpful
Best Regards
Smokey