NO ! dude. for 4.3 and 4.4, you can only flash back to the 2.67 ,root using Doomlord's method, and flash to rooted 4.4 ROM
Actually, it's very easy to do this step by step.
Use the search button please
sorry for my bad English
current phone: sony xperia z (rooted, unlocking bootlorder)
ROM: Slim-yuga-4.4.2.build.5-OFFICIAL-4060 (smooth as water)
(awesome kernel from dragonn)
Mod: Viper4Android (awesome audio mod)
secondary phone: Sony Ericsson x8 ( the legend )
Please hit THANKS button if I helped you.