I ended up being terribly disappointed with Once.
Wishmaster and Oceanborn are winners, though. And Century Child has its moments of brilliance and those of boredom.
Tarja is not attractive, sorry. I only value her operatic vocals, which were much more prominent than on later albums. She's no genius or anything, but they were damn distinctive and adequately performed. The band's sound is distinctive on its own, though. They have this unusual guitar tone and plodding rhythm with insane synthesizers. Kind of like Dream Theater meets power metal without wank and good riffs.
However, I had the immense disfortune of seeing a video clip of "Wish I Had An Angel." Wow. Someone kill that fudgepacker with the bass guitar. His antics alone ruined everything. Plus, the song has a shitty dance beat. WTF.