Are there any advantages to using a custom ROM

[demonix]

Beyond getting rid of any manufacturer bloat included as standard (I'm talking performance, less RAM usage and battery life (if that is possible) increases) as I'm certain that the EmotionUI is what is causing some of the issues with some apps since I know that a 0.3GHz difference shouldn't cause an app to crash with the same amount of RAM available.

Also, what would be the best ones to use on a Huawei Ascend Y300 and what I'd need to back up any essential data (accounts, apps and any settings data since getting APN data from giffgaff on android handsets seems to be pretty hit and miss) before starting the process of going to a custom ROM.

 

[demonix]

This said, whether or not an official build is available for the Y300 I have no clue.

There aren't any official builds, but there are unofficial builds for it from CM10 up to CM11 (although I might stick with 10.1 or 10.2 if 11 is a bit too much for the phone to handle), but I'd have to root the phone first since the backup solution you provided requires that first.

 

[demonix]

In theory CM11 should be better than CM10 for lower-end devices. Google specifically made 4.4 more efficient so lower-end devices could better support it.

I've downloaded the latest CM11 nightly build, the latest CWM that'll allow my to install it along with anything else that looks to be necessary, so I only need to obtain the software required to root the phone (which is required to use the suggested backup method) and unlock the bootloader (which might be a problem as the only one I've found so far installs a different recovery which I'm unsure if it can be used to install CM11 as the recovery required needs to support 4.3 and have certain fixes included) before I can get rid of this RAM hog Huawei have put on the phone.