There are some drawbacks to PI JDM motorcars.
They are designed for Japan, so the tropicalisation of their engine and running gear might not be effective enough for Singapore, even though Japanese summers are as hot as our sunny weather. Their audio system and antenna are tuned for Japan’s domestic frequencies, far removed from those used on our island, so the parallel importer has to improvise, replacing the integral head unit with an aftermarket set that usually doesn’t look or sound as nice. Another potential problem with unofficial JDM imports is their privacy glass, which has to be changed in line with LTA rules, sometimes with less than perfect results.
Then there is the warranty issue. The current industry standard for official Singapore-spec cars is three years of “protection” for up to 60,000km – 100,000km or unlimited mileage if the agent is generous. Parallel imported JDM new cars only have the basic factory warranty, which covers just the first year. Beyond that, aftersales support might be a hit-and-miss affair that depends on the size and commitment of the outfit that sold the car.
If there’s a product recall to fix a serious or potentially dangerous product defect, the car manufacturer does it through its authorised dealers and supplies them with the necessary parts/procedures to rectify the fault, free of charge if necessary. Parallel importers have to find their own way, and more often than not, tend to pass the rectification cost/problem to their customers. 
