We primarily camped, but we had a couple of hotel nights as well. We finished at the BMW RA Rally, which was all camping as well. It’s possible to do it either way.
Six or seven days on the route would be best depending on how much sightseeing you want to do. It is also possible to make up time by taking pavement routes vs. remaining on the official track the entire time.
In my opinion, the middle 30% is mostly a ‘connector’ section. It’s less scenic and has a lot of residential roads, but there is a lot of historical and tourist places to see, so it’s still a good part of the trip, just less remote. The beginning and end are the best parts for more of a back-country experience.
We didn’t realize how long it would take to put the miles in on the track, which is how we ended up pushing it. 180-200 miles per day doesn’t sound like a lot, but it’s too much when you’re on the trail – it made for very long days and we couldn’t stop much if we were going to stay on schedule.