Sounds good, but...what actual difference could one expect to hear with the Icom antenna, vs something like the Diamond RH77-CA which IMO does very good on airband?
Heh, it's what you CAN'T hear. The Icom FA-B02AR airband transceiver antenna is very narrow. That means it is terrible at receiving the FM broadcast band. Likewise reception of amateur 2 meters, and vhf-hi pretty much sucks. UHF is also a wash.
On some of the older dual-conversion scanners (and even some new models with 1980's style dual-conversion), I used to get hammered by Amateur 2m packet transmitters desensing my airband monitoring. Even with the Uniden and GRE oem antennas. Even worse with the Diamond RH77. Put on the narrow Icom, and it's a whole world of difference. No attenuator!
That means the typical weak front end of a scanner is less susceptible to overload and desense from neighboring services surrounding vhf airband.
The Diamond RH77-CA is VERY GOOD at receiving neighboring services, being wideband in nature, and this may not be the best fit for your over-sensitive scanner.
Even on my treasured older Unidens, I noticed a lower noise floor overall, and usually a quicker-to-open squelch in congested rf areas. Kind of bulky on my Icom R6 with adapters, but I feel it is worth it there too.
It sounds like marketing, but because of that lower noise floor, the overall performance of the shorter narrowband Icom antenna, is equal or surpasses that of the Diamond *in this airband application.*
