When should we use Radix sort?

Question

It seems Radix sort has a very good average case performance, i.e. O(kN): http://en.wikipedia.org/wiki/Radix_sort

Yet it seems like most people are still using

Answer 1

Here's a link which compares quicksort and radixsort:

Is radix sort faster than quicksort for integer arrays? (yes it is, 2-3x)

Here's another link which analyzes running times of several algorithms:

A Question of Sorts:

Which is faster on the same data; an O(n) sort or an O(nLog(n)) sort?

Answer: It depends. It depends on the amount of data being sorted. It depends on the hardware its being run on, and it depends on the implementation of the algorithms.