Custom ROMs : Advantages and Disadvantages

Advantages

Updated versions: 
You can flash the latest  Android versions according to your device's specs which can make your old phone look new. You can upgrade to a version of the OS that has not yet been released for your device, or never will be.

Personalization: 
There are a number of features that can be customized to suit your taste and working environment. For instance, Custom themes can bring a new look and feel to your device. Pie controls can be used instead of buttons or on-screen keys.

Improve performance and Battery Life : 
Custom ROMs are often faster, more efficient, and use less memory because

• the developer ripped out useless bloatwares, such as carrier installed apps or manufacturer's unwanted gimicky apps.
• the developer optimized the kernel. For example, an undervolted kernel can provide a much better battery life than the stock one.
• we can overclock or underclock the processor according to our needs

Install Apps on SD card: 
This is currently not possible with stock ROMs. If your phone ran out of space occasionally when install new apps this is a killer feature to have. Most custom ROMs nowadays come with the ability to install applications to the SD card, called Apps2SD (or A2SD).

Better signal and quality:
Custom ROMs help you to improve your base-band which in turn increases the signal and quality of your phone call. It also improves Wifi connections.

Disadvantages

Bricking : This is one of the main reason why people hesitate to root their devices. Some devices may become useless if you did not root properly and the only option left with you is to get a new one as the manufacturer will cancel the warranty if they find any attempts of rooting.

Loss of all Data : When you install a new custom ROM, it will clean up your system and therefor you will loss all your installed apps and data. However this can now be overcomed by installing few apps like Helium-App Sync and Backup , App Backup & Restore or you can always make a Nandroid Backup.

Bugs : 
Custom ROMs could have bugs… but then so do the stock ones. However, in case you do find a bug, you actually have a 2-way channel of reporting it - post in the ROM forum and you will more than likely get an answer back and your bug acknowledged. Try doing this to your phone manufacturer and see if you can get past the first level of outsourced monkeys, let alone actual developers. Milestone builds of Roms (stable ones) can be flashed which contain less bugs than the Nightly Builds.

Reboot : 
If the rooting is not successfully done, the device may enter to an infinite loop of booting. But you can always flash a new ROM  to make your device functional again.



Thus, the benefits of the custom ROM outweigh the disadvantages or risks on flashing Custom ROMS. Who doesn't love open source after this? So guys root your android devices, apply tweaks, customize and stay High on Android.