Well you can easily find out what Ka guns they use, the 985 has tech mode and you can see the frequency hence you will know what kind of radar gun they use. And if they shoot Ka 34.7 or Ka 35.5 those guns do not use POP.
In addition, I do not think your OLD RD will pick up POP, POP is a whole different beast.
Honestly your recent two threads, you can not make a judgment because you have way too many variable, first even though you have them far apart, that is no guarantee that one can interfer with the other, then you have one pointing in a completely opposite direction, of coarse you are going to have differnt results, you might as well put the other in a metal box and criticise it for not picking it up.
Granted it was difficult to understand how everything happen, I just had a difficult time understanding what happened.
Bottom line if you ewant to make a comparison, and you have a cop shooting radar in stationary mode, use one detector and see the range, then tun off that detector and replace in smae position with other and repeat.
You do not see GOL making comparision of RD with one RD pointing foward, and then have another pointing in the rear.
Depending upon many variable, primarily if the radar is not shooting at you hence there is NO threat to you, you will not get an alert unless there enough objects to get reflections from towards your front RD.