The Preamplifier will cost you some dynamic range. An ADSB filter would be called for. The preamplifier gain should be "about" 3dB to 6dB more than the combined loss of any filters and coax which sit between it and the dongle. The dongle is rather narrow band for ADSB. AirSpy's do a lot better with essentially the same front end, R820T2 vs the more usual R820T.

{^_^}