But I do like the look of the ones Specialist Firearms Command (SO19) anti terror police use here in the U.K..
The military used to use Harley Davidson MT350.
Power: 30 bhp (22 kW) @ 8000 RPM
Engine: Rotax 348 cc Air-cooled single cylinder four-stroke single overhead cam
But the modern day Metropolitan Police SO19 use BMW F800GS.
Top speed: >200 km/h (120 mph) (F800);
Engine: 798 cc (48.7 cu in), parallel-twin, water cooled, 4-stroke, DOHC, 8 valves
While the Special Escort Group (SO14) use Honda VFR1200.
Top speed: 157 mph (253 km/h)
Power: 127 kW (170 hp) @ 10,000 rpm; 148.94 hp (111.06 kW) (rear wheel)