The Jap import cars they sell are UK registered. I haven't read the whole blurb so I don't know about the bikes.
I bought a Mazda 323 from a Brighton back street dealer some years back. That was a Jap import. It had just over 40k miles on the clock (although the odometer was in km if I remember correctly.)
When I took it to the Mazda dealer for a service, the mechanic showed me the difference between mine and Eurozone spec'd ones. Things like a single row, skinny camchain on mine as opposed to a double row heavy duty one on a UK 323. Other things were obviously much more cheaply made.
The reason explained to me was Japan's strict regulations regarding used vehicles and their equivalent of our M.O.T system being so strict that cars over 4 years old and above 40,000 miles were rare, so it wasn't worth building home market vehicles to last as long as some exports.
That said, it ran like a Swiss watch for a year and another 16000 miles before I sold it privately for not a lot less than I'd paid.