I just bought an N8013 from Bestbuy and was planning to keep it stock until the official KK update from Samsung.
Curiosity got the better of me and I installed Philz Touch with Odin and used the 4.1.2 for a couple of days while reading up on Omni ROM and Gnabo ROM.
Today, I decided to flash it to Gnabo V5.5 (4.4.2) and couldn't be happier with the result. The tablet really feels great with the update and the process of the update was very easy.
A couple of things are different from stock.
1. No haptic feedback with Sammy keyboard. Haven't figured that one out yet (yes looked at everything haptic related)
2. The 5GHz band didn't appear to be there at initially......however..... I discovered that the lower 5 GHz channels on my Tomato router (RT-N66U) worked fine when entered into the router manually. The 2 digit channels, such as 44 etc would work. However, the 3 digit channels would not. Auto channel on the router for 5GHz never worked and I assume it was picking a 3 digit channel. Once I set it to channel 44, the router saw the tablet and vise versa. No connectivity issues observed so far.
Other than that, Gnabo feels solid, and I like the layout just fine......if this was the last update for N8013, I could live with it no problem.