M3E RTK - Base Station?

Our company is currently in the process of purchasing a new drone as our current one is malfunctioning. We received a quote from one of our software reps and it included the DJI Base station. However, we have numerous Topcon Base/Rover setups and I was curious if it is possible to use the RTK drone with a 3rd party base station like we have. If not, what advantage is the RTK to us without it being connected to something that provides corrections? 

We currently use a P4Pv2 for all our aerial mapping and I go out and place GCP's around the job site with my base/rover, and then process the data in Pix4dmapper. Assuming we just bought the drone itself with the RTK module, would we be gaining any accuracy? 

Thanks,