It will have no problems although you may have to get a plug adapter for the charger (couple of quid) be careful of the capacity, the 15Gb ones can be bought for around £220 in the UK and at today's rate you would be payiong £229 for $400.
If you order by post there will probably be 5% ish duty + VAT added to the TOTAL price. Shipping ain't cheap neither. If you know someone who is trotting off to the States, far be it from me to lecture about declaring the Ipod at customs.
Ism it me or are people happy to pay £300 for what is effectively a 20Gb hard drive? ;-)))