I confess, I mainly bought this for my three and a half year old because I'd always wanted one myself, but she's loving it. There are plenty of detail items, and while she's a little small to work the lift as yet, there are still plenty of doors and stairs to move people around.
You do need to allow a good couple hours to construct the castle, and there are a couple of sections which I've not convinced to match up perfectly, but as always with Playmobil it's solidly constructed. We've actually found that keeping it apart in sections (towers, gatehouse, two sections of battlements) and spreading these round the floor gives her far more play access, and it's also easier to pack away onto a table at the end of the day.
Lots of accessories, including plenty of people.