It's not a competition really...more of a personal preference.
I'm not an expert on Gyaru or Ulzzang style. It's just that people have been asking me about it so here is my personal observation.
What they have in common-
Perfect looking skin
*sorry no circle lenses in this pic but I'm wearing upper and lower lashes see!?! :)
go to the next page for more!
Gyaru(Japan) requires more work on the hair and eye makeup than ulzzang. False eyelashes is a must!!! (top and bottom!) Lashes are usually not cut and are longer than the normal eye width to give either a droopy eye effect or just a wider eye. Gyaru hairstyles are also more fussy- and haircolors tend to be varied (black is not common with gyaru). Nude/pinkish nude lipcolor is the norm.
Ulzzang(Korea) tends to focus more on perfect looking skin and natural looking shiny hair(although some dye their hair too). Lip/cheek tint is commonly used, although nude lipcolors are in too. It's a very toned down version of gyaru(although it should not be mistaken for one). Simple lined eyes- False eyelashes are also used but the ulzzang look requires the natural looking(not so dramatic falsies unlike gyaru)
To give you a better sense of the difference
Gyaru *style has a lot of varieties- I'm only choosing some of the common ones
Notice that most of them are wearing underlashes?
Another good example is the style of my favorite fellow bloggers:
Note the difference in their eye makeup
Gyaru- Anz, Cindy, Xixi (quit) Yapo (early posts, she's now more into jap street style)
Ulzzang- Rin and Miyake (current look) justine stopped blogging :(
Again I would like to stress that I am not pitting these two styles against each other. I am just showing you the differences between them to avoid confusion since some of you are asking me what's what already
Hope this helps!!! xx