Without using having any experience with the Amplifire and based on your described experience I'd have to agree that there is a latent switch with the AX8 when switching from one amp with various effects to another amp with another set of effects. But you typically can set up most amps in a clean state using input trim and drive levels and using a scene controller to adjust those parameters to get to high gain. And THIS is how the latency is usually mitigated to an acceptable amount. This of course comes with the caveat that jumping from a Fender Twin, with a compressor and spring reverb to a 5153 with a tube screamer and delay on will be a little more noticeable. And there are some tricks you can do to hide the gap, such as having your reverb wash a bit to cover the switch.
@Moke is really good at this type of stuff.
All that being said, I still use a clean scene with a Morgan AC and dirty scenes with a Marshall. I find myself fumbling more to switch to the right pickup at the same time as stomping the preset and it's pretty clumsy for me. And for that reason I always set up my main dirty rhythm scene so that I can clean up just by switching to my neck single coil and turning the volume down.
It's ironic because when I was young I started with a cheap Crate amp that had a clean and dirty channel with a foot switch. I'd stomp on the amp channel switch and a chorus pedal at the same time and switch to a neck pickup. Then I got an old NMV Marshall and figured out that turning down the volume knob cleaned it up. It actually took about 6 months for me to figure it out and found out a few years later that's how it's always been done...lol. So, I'm used to that for the last 30 years but always wishing to have one stomp to switch to another rig......and here it is now - my AX8. And I still NEED that clean up capability via the guitar volume because playing dynamically or playing the amp had become part of how I played.
We're in an awesome era to be guitarists. I have a cranked tone with studio effects playing at bedroom levels. Everything I wished for. The latency thing is a minor thing that I've always had to deal with so I'm unbothered and have learned some tricks of minimizing it. I've never had a professional pedal board that switched amps for me but I wonder if those have a tad bit latency when switching.
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