Right off the bat, what jumps out at me is the red and white stake on the trailing leg. The Pak-40 was a direct fire weapon. The red and whites are used as aiming stakes during indirect firing.... they are incorrectly painted... they should be as shown on the box art...
You also would not expect to see all those rounds haphazardly tossed on the ground in the area behind the gun...
Still, overall the finish on the gun and the painting of the figs looks pretty sharp to me... although, what the heck is the guy that is kneeling next to the right side wheel supposed to be doing??