Yes, quite impressive!
What bugs me is that I read somewhere one of the achievements
involves getting to all the bells without paying any guard. That is the one I'm missing (and all the greek letters C)p).
Now the main issue with that is one must probably reset chapter 3 saves in order to do that. And I'm not quite sure whether all the other achievements remain intact.
Achievements are separate from chapter saves, meaning you can replay to your heart's content. Also, once you find out
how to get that specific achievement, you can get it very quickly after starting over.
Also, regarding achievements, I have a question about the knight helmet one in the picture I posted. It appears to replace the Heroic Dance achievement from the PS3 version, as the mini-chapters are not in the PC one. My question is, I can't really remember how I got it. For some reason I think it had something to do with the
secret levels under the entrance to chapter 3,
but I can't recall for sure.