Results are in...

30A Machine torch cut on 3mm steel...


30A Hand torch cut on 3mm steel (top line only)...


20A Hand toch cut on 1.5mm steel at a good speed...


The same cut but showing the reverse side (top)...


The back dross knocked off easy, there was none on the front, one side of cut was bevelled, other was straight, i think this is normal behaviour.

SO I will be ringing the suppliers for a smaller torch more suited to 20-50A cuts than the 50-100A torch they supplied

I have also found another user who was sent a massive torch and is now just using the hand torch.

This seems to be the answer.