I'm using the MZ607 with the original (not rooted) 4.0.4 rom and by browsing there are always weird lags... But I'm using this tablet since early 2013 and I have lots of personal files which I need to backup before update.. Before start doing it, I would like to ask to the people who did it already if have you feel any improvement in the OS performance? any bugs detected?
For the most part I would say it gives a better user experience, based upon the last 24 hours of use.
Bugs
The dock application has got even worse. I wasn't too bothered when they ditched the linux mode with the ICS update but a lot of people were. I still found it very usable, if a little slow as the tablet was working overtime to send output to two HD screens (it's own and the TV). On this latest JB ROM the dock is pretty much unusable. It doesn't rotate the screen to landscape automatically (Moto docks hold the tablet portrait, the rotation was previously performed electronically for you) so you're only using about 1/2 of the screen. Tipping the whole thing over rotates the screen as expected but chops off the top of the screen (it used to chop off the bottom intentionally) making most apps unusable. If you used your tablet to rent films like I did that's now a no-go.
The speaker orientation still isn't fixed.
There's a GSM signal indicator constantly on the notification bar showing no signal as the ROM comes from a 3G tablet.
Google Now is much, much slower to load than the old Google Search.
It doesn't appear to like the Google Experience launcher which might have fixed above. Just force closes if you install it.
Pros
The wifi indicator seems to be a bit more honest now and connection is said to be more stable.
Project butter has made the UI more polished. Everything transitions so much more fluidly.
For the most part the tablet seems less laggy. Still not perfect but I'd say better. The time taken to rotate from portrait to landscape is vastly reduced. Returning to the launcher is faster and opening every app except Google Now (mentioned above) seems faster.
Chrome seems to work faster and more consistently - maybe it needed some APIs from JB to work right?
Browser seems more consistent and is still there, many JB devices lost the stock browser in favour of Chrome which I find more resource intensive.
If I discover anything else I'll post up again. Overall I'm happy I did the update.
