It was heavy and having difficulties on maneuvrability although she has its own propulsion. No need to mention the number of crew and time to be ready to fire and difficulties to change the position. Complexity made Panter howitzer open to malfuctions on field so Turkish Army has stopped production when it was ~40 and MKE Yavuz truck mounted howitzer project was borned. It uses same Panter gun on a truck and it just need 1minutes to be ready for fire, 1-2minutes to change position with 90km max speed. 150 MKE Yavuz in order. I suppose All existing Panter howitzers will be upgraded to Yavuz.
As far as I know, A few Panter howitzer is given to Pakistani Artillery school as a gift or cheaper prize under the friendship of two brother states. I don't suppose Pakistan ordered Panter howitzers officially.