OmniROM, one of the many big name custom ROM's floating around the development scene has now added Android 5.1.1 support to their nightly builds. While they have been uploading builds of Android Lollipop for some time, naturally their users were anxiously waiting for Android 5.1.1 to make its way into their favorite custom ROM. The team behind OmniROM claims to have been working on this for some time in order to achieve a level of polish, and thankfully that time has arrived. Unfortunately OmniROM 5.1.1 nightly builds are not supported automatically for all devices, that will be up to the devices' respective maintainers.
For now owners of the ASUS Transformer Pad, ASUS Transformer Pad Infinity, Google Nexus 4, Google Nexus 5, Google Nexus 6, Google Nexus 7, Google Nexus 10, Oppo Find 7, Oppo Find 7a, Oneplus One, Sony Xperia Z, and the Sony Xperia ZL will be able to flash the latest build of Android 5.1.1 OmniROM on their devices. The development team does advise any users of unofficial or homemade builds of OmniROM to do a clean flash (data wipe) before flashing to the latest official 5.1.1 build. It's not clear what bugs may exist or which features may have been left out during the switch to Android 5.1.1, but likely any issues will be ironed out as the general public began to test the new builds.
It is worth noting that the "nightly build" status brings along some important things users should take into consideration. OmniROM makes it clear on their website that only finished features make their way into nightly builds, and that they aim for release quality stability when working with nightly code branches. This is because so many users now prefer nightly builds to have access to the latest features, that OmniROM hopes to give the large group of users a solid experience. That being said, mistakes are made and tweaks are needed as nightly builds are improved and updated each day. Best recommendation for users interested in trying out nightly builds for any Android custom ROM is to create backups of apps and personal data before proceeding. Being known for past releases with features such as hotword customization and multi-window app support, this custom ROM is definitely worth trying out.