I just have to chime in.
For Sun N Fun 2018 and 2019 as well as Oshkosh 2018 and 2019 we (and again in 2021) we have at our booth the "Take the Big Brand Challenge". It's a lot of fun to do and it takes 3 minutes. We have a GMA345 next to our PMA450B and we ask 4 questions:
1) Do you want Bluetooth?
(YES)
2) Would you like to hook up two devices at the same time?
(YES)
[Sorry, the GMA345 can only hook up on a Bluetooth device. Once paired, you won't see it available for any other device]
3) How do you change Music Distribution?
(You push the button that has Music Symbol and SEL on it)
[Sorry, there is no music distribution. You can only select what everyone hears...NOTE: there is a switch on the rear of the panel that if selected, then passengers will always hear music #2]
4) How do you turn on GARMIN's 3D audio?
(I don't know)
[Reference the laminated card that comes with the audio panel to access the 10 (ten) what I like to call the "secret clubhouse handshakes"]
GARMIN makes phenomenal stuff, I have tremendous respect for what Gary and Min had started and what their team continues to do today. But, IMHO, I can't think of a single reason to purchase a GMA345 instead of our PMA450B EXCEPT to save $500! So that might be legit but holistically comparing the cost of the hardware and installation on a panel upgrade, that is a very small percentage of the overall investment.
And I didn't even mention our "Alternate Intercom Function"!
Thanks for letting me participate in the forum, there is so much good information here, I'm proud to say I'm a member.