I have 3 French appliances (Miele) which I brought to New York: 1
dishwasher, 1 dryer & 1 washing machine.

Has anybody been successful at hooking up this type of applicance here
in the US?
They take 220V, 50Hz and 3000W in average each( I have 4000 W
transformers which seem to do the trick even if they won't convert the
50Hz into 60Hz (any risk here?).
Would it be better to install a 240V line directly to the machines
instead of using the transformers?

Also, the plumbing side is somewhat challenging (the washing machine
and dishwasher both take 3/4" instead of the standard 3/8" here) which
I overcame in piling up some plumbing adaptors. A little leaking
though.

Please HELP if you survived such an experience.

Thanks