Alex, very much looking forward to your take on the A units. Lots of people here frustrated with losing the engine ID on power up. I appear to be the only one with a different problem. Both of my A units experience frequent stalls when starting up at low speed. Lights flicker, then unit stops and either resets to cab light on and smoke unit on, or I get the dreaded single blinking cab light. Since only one stalls at a time, the other one tries to pull his stricken brother along! However, if they get past initial start-up without stalling then they can run all day, even at low speed, without stalling. Checked everything on layout and other Legacy engines continue to run trouble-free.
mine didn’t have that issue, but I do have the issue with both A units losing their engine IDs. As for yours I would send them back to be looked at.