It's definitely worth considering, even I I've actually decided not go to a metal festival this year.
Interesting would be:
My Dying Bride
On The other hand, it would be quite expensive to go there for just 4 bands (and Tristania disappointed me 2 times out of 3, form where do I know they'll be better this time?). and again I know I'd be paying not for the bands I want to see but for expensive bands I don't wnat to see (Apocalyptica, Within Temptation, Avantasia).
Edit: And I'll never undestand why festivals where only METAL bands are to play are called masters of rockor something like that..that's quite misleading