I just noticed I've already got 105 hours on this game. Most of it is from character creation and even in Act I I've only seen the content that was available at EA release...Looking forward to what has changed/added in Act I.
Think I'm going evil party first, Larian games typically offer plenty of fun playing this way.
Steam marks me at 500, but realistically speaking at least half of it is idle time sitting on the main menu or with the launcher opened in background (yes, it's counted as playtime as well) and so on.
Still, I'd say that I probably spent more or less 200 hours between a bunch of playthroughs trying different classes (the first one was around 40-50 hours, the subsequent ones get progressively shorter as you become familiar with what to do and in what order).
I never made a secret of having a whole freaking list of complaints about some questionable (when not downright bad) decisions Larian made, but overall I'm confident the end result will be at very least a solid entry in the genre and worth spending time on.
Not sure if it will ever been considered an instant classic and one of the all-timers on the other hand. Time will tell.