In my tests over the summer, this little 210mm 2.5 dBi + LNA antenna noticeably outperforms the 1448mm 9 dBi DPD Productions 1090 MHz antenna and the 660mm 5.5 dBi FA 1090 antenna with Uputronics or RTL-SDR filtered LNAs at the receiver - not at the antenna.
This is for a challenged station basically surrounded by tall pine tree forest. Aircraft count and positions and even max range improved with this little guy! The large DPD antenna came in 2nd place with better avg max range and positions than the FA antenna.
In terms of price, the Active Diapason costs about 10% more than the DPD (for US customers) and performance is about 10 to 15% improved for my weird site. But the FA antenna clearly takes the crown for price to performance winner, by far.