It depends upon what is available for your device and what you want out of the firmware. What I will suggest is looking at the device specific forums at XDA.

It depends upon what is available for your device and what you want out of the firmware. What I will suggest is looking at the device specific forums at XDA. You will get an idea of what is available and what is reliable. Personally, I shy away from distributions that don't include a "what works" and "what doesn't work" section in the first post. I also prefer "official" distributions. At the very least, it is easier to track updates. The next filter I use is feature based. In this context, look for distributions that don't include Gapps and offer additional privacy enhancing features. Once you have something that you think you want, read the thread for the distribution. It often reveals pitfalls, variations within the model, and variations between carriers. These pitfalls exist even with the popular distributions, which is another reason to check out the forums. I went with OmniROM this time around, but I have been happy with Resurrection Remix on other devices. Some devices have nice alternatives that are specific to them. As an example, I use KatKiss on the Asus TF300T. For a while, it was running a more recent version of Android than my much newer phone!