I'm planning to go up to Hokkaido in a couple of months, but one
question I have is about driving times.

First, the wife read in a guide book that car navi cannot be trusted
there. The exact reasons were not described, but I would think barring
being in a deep valley, there would be no reason for it to be any
better or worse than anywhere else.

Second, what are driving times like? She found a web page that seemed
to use 50 kph as the basic speed for all the time calculations. Are
the roads really that bad/windy/full of traffic lights, or was this
based on everything being under a metre of snow? We're planning on
going to Hakodate, Niseko, Otaru, and, umm, some mountain place that I
can't remember but the middle kanji is RYOU/yoi.

TIA,

Ken