Iv'e used the Skyrim vanilla UI for the majority of the time iv'e had the game since around it's release. I tried Sky UI & didn't like it all that much as i was used to the vanilla version & found it quite confusing due to the sterile appearance of the UI itself. But due to some mods needing it, i have had no choice but to use it.

However, playing Oblivion again, i find the mod, DarNified UI, a much more welcome & much better UI in this game.