Here are some advantages of santoku:
chop() always covers the whole range of the data, so you won’t get unexpected
Flexible labelling, including easy ways to label intervals by numerals or letters.
Convenience functions for creating quantile intervals, evenly-spaced intervals or equal-sized groups.
Convenience functions for quickly tabulating chopped data.
These advantages make santoku especially useful for exploratory analysis, where you may not know the range of your data in advance.