I think that the Trig is the easiest to use transponder out there, compared to the other offerings mentioned before. I've used them quite a lot and once you get used to 'twist-enter-twist-enter-etc' it can be done really quickly. The only other solution that might be slightly easier is the KT74 or the GTX345, where you've got the numbered buttons below the screen. The downside of that is that you have to keep looking to see if you've pressed the correct button, whereas, with the Trig, you can increase from 0 to 3 for example by feel. Also, I prefer the rotary selector for the modes, compared to the somewhat fiddly buttons on a GTX345 or the other Garmin options. I find that with a Garmin transponder I'm spending more time (only seconds, but still) looking at the screen to see if I've done it correctly than with a Trig.