Thankyou so much Mr Rusty and everyone for your very helpful replies! I am so glad I asked the APUG oracle because before then, I was probably
about 24 hours away from trying to connect the units with a 240V IEC cord and that would have been bloody disastrous! So now I will not be touching
any of the cords until I take my good advice to a local sparky, just to double check absolutely everything before I go for the stepdown transformer option.

I may end up having to get two of the 1500W transformers so that I can move around the shooting area with more flexibility. I'm sure that
one day I'll buy more lights as well, possibly with higher wattage again, so if it's okay to use any *higher* wattage transformer on a lower
wattage light, I can maybe think about getting the right combo to allow for future added units to my kit. AND I would then be set up for
shooting in the US any old time I felt like it, should I ever be working there! Which I hope I will. The price of buying extra stuff to make
these lights work is just going to be a necessary evil, but hey, live and learn