This comment applies to new units: AXISS Audio, the Accuphase importer, has reduced the MSRP by 20% in the US for new Accuphase equipment. Although, the US prices are still higher than the domestic MSRP in Japan, when you add all the other costs, the gap gets reduced significantly. In addition, it will be difficult to get the 110V version in Japan and as others said, in case of need for service you will need to seek a third party as the official Accuphase channels, most likely, will not provide support due to the unit being a gray market import.
Disclosure: Locrian Audio is an Accuphase dealer.