595 hours (most of that's EA, about 100 hours since full release.)
I've reached Act 3, though I've hit what may be a game stopper, or may at least need to revert back several hours to an earlier save.
I'm playing with a Sword Bard, aka a Blade, the same subclass I beat BG2 with.They don't have quite the damage output of other martial classes, but can get an insane ROF with Haste + Flourish + dual-wielded hand crossbows. And they get access to a large pool of skills, along with the 'Jack of All Trades' feature which gives a bonus to all skills they are *not* proficient in. And some very useful spells, though typically not damage monsters like Fireball.
But they do get Cloud of Daggers, which is a crazy amount of fun. Experiment to try at home: Have your mage cast Grease (or other 'difficult terrain' spell) and have the bard cast Cloud of Daggers at a choke point. As the enemy comes through they take damage from the cloud and/or slip on the Grease (and take more damage when they get up.) If they do make it through, knock them back through the Cloud with a Flourish or Thunderwave. Or have Karlach toss them back into/through the Cloud of Daggers. Rinse and repeat.