Congratulations on your new phone. Please visit the tutorials forum: [Only registered and activated users can see links Click here to register] There is a lot of information on there.
The iNew v3 is a well-experimented phone with a lot of custom ROMs popping up, left and right. Unfortunately, there have been some incorrect flashes, giving many v3 owners problems.
It would be best to create a backup of your phone before you try anything out. There is a method for it in the Tutorials forum. Secure a reliable stock ROM as well, to be extra safe.
Athos has done a great job but I prefer to state the obvious. As soon as you root your device or put a custom Recovery or ROM on your phone you have voided your warranty for most sellers.
Unfortunately the best backups or best tweaks are generally achieved by having a rooted device.
My advice if you want to go down this path is don't......wait and read a bit.
Only when you understood the reasons and methods, then have a go.
If you have a problem with your new phone then it should still be a warranty claim and depending on what you report you can always try a factory reset.