Really interesting topic. I have had radios from all the main brands over the years and currently have 3 in use.
A Futaba 3VCS with FASST, used for cars. An old Sanwa RD6000 6 channel radio and a FrSky Taranis XD9 plus SE on TBS crossfire, used for Drones, but soon - on my 3D fixed wing aircraft as well.
I'm not a fan of changing things, just for the sake of it. I'll only spend coin if I can see real advantages by doing so.
Opentx is something that I first came into contact with during the first lockdown, so I'm still reasonably new to it. However, there are obvious advantages to an open source operating system. The obvious one is how powerful it is, enabling a high degree of customisation. It's a little like Android vs IPhone.
Intuitive systems definitely help users get where they want to be quicker, but people are all different. Futaba's tendency to split functions up over different parts of the menus can be frustrating, but foibles are something all the systems have.
I'm never likely to change from my 3VCS for surface use, but for flying, Opentx is likely going to be my first choice for the foreseeable.
The obvious advantage to these newer, Opentx systems are higher performance and lower cost. The latest colour, touch screen variants allow much easier programming, which is terrible news for me because I've just got used to Opentx Companion! This is increasingly redundant if you have a giant touchscreen built into your radio.
My 35mhz radio is no longer permitted at my local club, so I'm forced to change the receivers over to my FrSky stuff. I'll get over it. So far, the change over is smooth and Flaperon mixes and throttle cut functions are readily setup in Opentx.
Looking at some of the lower end Futaba stuff made me wince - it's very difficult to justify spending that sort of money when you can have a better specced radio master for the same dosh.
As for quality, well, I believe my 3VCS was state of the art when I got it and higher quality is difficult to find. My X9D Plus SE has excellent quality overall - ballraced Hall effect gimbals - the only let down being a slightly hollow sounding case and buttons on the front that feel like they're about to fall into the gubbins. Very picky, minor complaints.
Looking at the signals produced from ACCST vs Futaba's FASST on a scope, there really doesn't look like much difference - bar the fact that they are inverted to each other. FASST is supposed to be the king of range (definitely bourne out, for surface models) but my crossfire system/receivers are good for >25km. For LOS flying, FrSky X8R receivers are good for >4km. You'd need a pretty big aircraft to fly at those kind of distances!
At my local club, the jet flyers are using FrSky stuff on ACCST or ACCESS/Archer and have zero problems.
As an old school RC enthusiast, I still look at Futaba as a likely answer to all of my RC requirements, but then my bank account says 'nope'. And that's without adding a wife into the equation.
Edgetx will be the next thing, just when I get into my groove - you can count on it.