I have an Apollon IET400A. No on/off pops at all using the 12v trigger. I have not used autosensing.
The opamp rolling feature is a non-issue. You wouldn't be able to hear a difference between different opamps.
I purchased their Purifi Eigentakt 1ET6525SA Lux Stereo Amplifier with Sonic Imagery 994 opamps and I haven't had any popping or anything but pure pleasure from playback. I still think there isn't anything like a handmade production line like the one Tibor and his team have. I think their only flaw is there lack of response to their customers but we are talking about Slovenia where things are done differently as to be expected. I think its an excellent company, making great products, that needs a new customer service team to just handle customer queries, and they'd stand above many others. I'd buy their higher end products without question. Thank you Tibor M. Enjoying greatly my new amp.