5 minutes, interior + dof.. not bad at all if you check components I used. 1600x1200 image required about 500MB of memory so you better get
card which has at least 1GT.
*Update* New version required just ~190MB

Intel® Core™ i7-3820 - Gigabyte GA-X79-UD3 - 32GT RAM - ASUS nVIDIA® GeForce® GT640 2GT - Wacom Intuos5 M Touch - Windows 7 Ultimate x64 - Modo 701 - ZBrush 4R6 - Rhino 5.0 - Maxwell Render 2.7.20 - Octane Render 1.1.