My Pfaff "electronic" ironer runs on 220v/50hz, and is quite happy on this side of the pond. Indeed at a recent service call, the unit was fine except for user caused damage and a few other minor, but normal things arising from age.
Pfaff ironer pulls about 2500 watts for heater, and 90 watts for the motor. Boiler for steam uses 1000 watts. Unit has a standard Amercian dryer "220v" plug, fitted on when purchased from the original owner's family.
Back to the Miele:
IIRC, the units are already in the United States. Seller states he purchased them to have installed,but things didn't work out.
Am wondering though how and why seller has UK Miele appliances in the United States. Unless he moved house from the UK and had a VERY generous moving allowance, inculding a very spacious shipping crate.
Being as all that may, it is not uncommon for European appliances to arrive on these shores. Aside from my Pfaff, have seen serveral "European" only Miele units on eBay, as well as AEG and a few others.
Certian Miele appliances do not care how they get their 220v. Older 220v models of the Miele ironer for instance,will run anywhere in the world on 220v power.
Didn't notice the units are only 6kg capacity. In which case I wouldn't bother, unless one nabbed them for a good price. Any savings from not purcashing Miele USA units can be wiped out by any special installation costs. If you do decide to go ahead, do yourself a favour and contact Miele USA and see if they can get parts and will offer serivce on these UK units. Should also ask, since these are MIB units, will Miele USA honour the warranty