How so? One button press, no? That's a whoooooool lot different than press hold followed by separate button press.
Edit to add: I want to be able to change amp channels with minimal fuss from the "effects" layout - I get that there are ways to do it with one button press from other layouts, but that then requires a little shifty foot hold thing to get to a place where you have 1-button access to the other three blocks.
If I were to use the AM4 standalone it would be:
(1) Drive block
(2) Delay block
(3) Amp block
(4) reverb Block
Ideally, I'd be able to either (a) use the amp button to toggle between Channel A and Channel B or (b) toggle on/off the input boost.
This isn't necessarily a deal breaker - but both of those functions seem like obvious and non-niche options for the "amp" button to do in effect mode. Or maybe I'm being Sasscha about it.