Its very long, even if you don't aim for "100% finish". Most reviews say 40-60 hours, don't know how accurate that is since there is no timer (or is there?) in game.
Thats why xfire is handy ^^
alltough most newly released game will take a couple of weeks before they can also track it and sometime the hours a bit off but i use it quite frequently since i registeredhttp://www.xfire.com/profile/agrash/
BTW, don't make the mistakes of investing in VIT or SPIRIT too much. Many do it beacouse its hard early so they think they need more of those, but later on you'll get so many items with bonuses for MP and HP that VIT and SPIRIT are not needed anymore, I say pushing both to around 15-18 should be enough, but I'm not sure.
Hmm for the moment ive just added all my points to strenght and vitality since i'm a warrior but i'll keep that in mind