There was a problem with the earth socket on the machine, but Weldequip sent one out next day as a replacement, in the meantime, a bit of filing sorted out the original faulty one, which hadn't been formed correctly during machining, so I now have a spare.
The torch etc. arrived today, so I set it up this afternoon and gave it a road test on some 3mm plate. Nice and smooth from the off, no problems with anything at all. I'm really pleased with the machine and confident that I made the right decision.