I have a near-new Syncrowave 200 that has been converted to liquid-cooling with a Bernard 3500ss unit and liquid-cooled torch. It will do 1/4 " alluminum quite easily by going slowly at first and letting the heat build up or you can pre-heat.

You complain of unstable arc and a counter that resets. Both of those are warranty issues. I think I recall that you posted about this same problem before. I would get warranty repair immediately. I supect a failed circuit board.

My counter shows hours used and records each arc start with no resets.

Let us know what your Miller warranty shop says.