The boy just went to bed, after completing page 141. Not quite half way after 2 weeks.
Still, he took a lot of days off in there, and hasn't really worked very hard on it.
Late Addendum: By the way, we did another major sorting push today. We had three cardboard boxes on the floor with miscellaneous small pieces. I was out of the house for some reason, and my sister was helping the boy find pieces. She got so frustrated, she took out more plastic cups and began sorting again. By the time we were all done, we'd spent about 2 more hours sorting and had filled about 15 cups with pieces. There are only odds and ends and easy-to-find pieces left in the boxes now.
This is why the set is meant for ages 16+, the sorting and hunting parts are the hardest things to do. I think it would be very frustrating for my nephew if he had to do the hunting for all the individual pieces. Even my sister finds it difficult, because she doesn't know which pile to look in or where the piles are.