How many hours can you get out of Dante's Inferno?

For a first run through Dante's Inferno if you play on normal diffeculty and really take you're time seeing all the sight and exploring every corner in hell, how many hours can you get out of it. I've heard that the game can be completed in 6 hours, but thats more if you hurry your way through as far as I understand. If you play really slow, exploring everything and such, how many hours can you get out of it for the very first playthrough?

I'd guess around 8

take me around 10 h on hard first time

I'd say ~8 hours. That's about how long it took me on my first Normal playthrough.

I don't really remember how long it took me, but I do remember really enjoying my time with it.