For me, how long I take during the inspection phase largely depends on the scramble. I tend to try to preserve blocks/place blocks(a.k.a. extended cross) or preserve corner-edge pairs so that may take away some time if I need to plan it out more. In general, though, I would say I take 5 seconds on average. I don't really time myself so I don't know for sure but it feels like about 5 seconds.