please correct me if i am wrong.
i thought for unbiased rendering, the longer the render time the better quality of the end results. how did you guess 10 minutes is enough to get this quality?
i like your lighting setup, nice speed test.
Usually if you sit back in your chair 20 unbias pass's will look quick good.. but you think "nah!" and let it go longer, usual 45 passes gives a nice result.. I'm not sure how many Solo did.
Its got a lot to do with what's in the scene, how much bump there is, textures oh and having a i7 helps lol