because there's not that much of a price difference between them mate. Get your facts straight before you go giving people shit about the stuff they want to buy for their cars. Pest
(Using Boost as an example)
Trust - 23,100 Yen (Control Unit - 13,650Yen) TOTAL: 36,750Yen
HKS - 26,040Yen (Control Unit - 13,650Yen) TOTAL: 39,690Yen
Defi - 25,200 Yen (Control Unit - 11,340Yen) TOTAL: 36,540Yen
Defi comes out the cheapest.