Hi Grumpy,
I agree with a lot of the points made, but have a couple to add. You must look for sun damage on a Jap import car. Faded seat cover and door card materials, gear knob decals and gaiter cracking and fading. Other then that they have been a good bet till now... However since buying my Jap import I have been to see a few other more recent ones (hoping for a lower milage example). I have concerns that the flow of decent Japanese Lupo GTI cars is drying up, and that in cases unscrupulous (or is that inscrutable?) exporters are being creative to continue to meet the ready UK demand. I saw a car in November that was "officially" registered as 33,000, but from wear and tear to all operating surfaces and door cards was around 100,000 miles higher than that (Also engine had masses of mayonnaise in the oil filler cap). I have seen the aluminium doors replaced with steel (so wrong glass too), and poor fit body panels denoting hasty covered over crash repairs.
Bottom line is that you have to be as careful whatever car you choose. Don't believe that because it comes from Japan and has a high forecourt price from a trusted dealer that it is what it claims to be. Take a magnet to ensure the aluminium is where it should be, check the interior wear is in line with the claimed milage, and check the engine (starting from cold) runs smoothly and quietly. A road test is essential to check gearbox, steering and suspension, as well as whether the engine pulls smoothly through the range. I hope you don't mind me stating what some would see as obvious, but I think the golden age of "perfect" Jap GTI cars is over and we all need to get much more canny not to get caught out...