I have just published a new Sudoku book from Puzzlewright Press called Donut Sudoku. All of the puzzles have the clues arranged in a circular, or donut pattern leaving the center 5x5 area empty. This is supposed to make it harder to solve the middle part of the puzzle. I'd like to hear from players whether this actually works. Are the puzzles better? Is the donut pattern pleasing to the eye? Should I continue this for my next Sudoku book?