at least mine better than someone who said "DEG are more popular thats hy people play". But what i said are facts. Some people love X Japan so much but they cant play them, while they like DEG too and since DEG songs is quite easy one (not complicated, dont need to be so fast) they choose DEG. u understand what i mean? my english too sucks to explain..
in techinically specs, IMHO, i still think no other band can compete x japan level of musical arrangement and composing. x japan use a simple chords (power chords) that make their song sounds easy, but if you wanna play it, its not like what you think. for example the song sadistic desire is easy, but when u reach the solo part, the slapping part, u nd skilled guitarist and bassist (definately above average) to play it.
i think the part that not many band can play x japan's is because of the xjapan music that need a really skilled guitarist to play their solo's, to synchrinize(xjapan speed is fast) and good vocal that suit the song. (lets ditch rusty nail ok, almost everyone can play it).
the double lid of xjapan like what guitar_phreak said,is the hardest part of x japan music, u really nd to be synchrinize with each other where not many guitarist can do that unless they have a good teacm with a great chemistry, then it works.