SAS also has a stable of HP-35s still. In the US, SOCOM did the famous trials resulting in the acquisition of the MK23 H&K. While many units have them and use them, no one solely uses the MK 23. The Combat Applications Group made a large purchase of Wilson built 45s, and still uses them as primary sidearms of choice. The Berretta M9 is widely trained with due to its use throughout the services now, and is used by Rangers.
The GsG9 also uses Sigs and Walthers, and still has a goodly inventory of S&W revolvers for use as needed.
One of the points of truly small elite units is that within the constraint of required consistency of what is carried in an operation, they have extreme flexability to use the specifc right tools for the job.