Being a test release, this ROM still has some quirks that need to be fixed, but it’s reported that it is a lot better than the last Android KitKat test release that leaked six days ago. The notorious multitasking bug is fixed, there are some performance improvements here and there and some graphic improvements. The fluidity is great, as well as the overall performance, which indicates that Samsung is close to releasing the final, official build.
Before flashing this firmware, beware that your data WILL be wiped, so backup your valuables before proceeding. This will not raise the flash counter, nor will void your warranty, so you’re safe in that aspect. You can find the installation instructions, as well as the download links in SamMobile’s post. The download is 1.5GB big, so you’ll want to make sure you are connected to your home Internet connection, and not on mobile data, to avoid further costs.