I don't have experience with the P3A with GL300C. I do know that when using a P4, the GL300C is the weakest Lightbridge RC that DJI has ever produced, based on
my testing. That's why so many P4 owners upgrade their antenna setup. However, MaxxUAS has evidence that each craft link may influence the power output of the RC. They say that the same RC can demonstrate different RF power characteristics when linked to different craft. I find this interesting, but haven't tested this theory myself with different combinations of craft linked to the same RC, measuring the RF outputs for comparison.
It's logical that P3A with GL300C would not perform as well as older P3A or P3P with GL300B or GL300A, given what I've measured for RF output from these RCs. But I cannot say for sure, because I haven't tested it. Maybe others have, such as MaxxUAS who has DJI hardware and the test equipment to compare things.
One mystery for me is how can P3A, P3P and P4 all ship with the same model GL300C? One of them has a PSA mode switch LABEL and the other two has a PAF mode switch LABELs. I realize both radios operate identical, each craft just interprets the same signals differently. But these two craft should have different labels on the mode switch, right? Yet DJI uses the same GL300C model number on these differently labeled RCs. Can anyone explain that? Is it possible the inside is different too? I'm thinking this is unlikely since they use the same FCC cert number, printed on the RC (I think that's the case).
We should move this to a new thread.