I remember stumbling upon Ikeya Formula years ago when I was building my Altezza. It was in one of the Hyper Revs issues that coverage an array of performance parts already offered in Japan. Like many, I would study each page one by one, trying to decipher the Japanese language.
For VIP cars or Drift builds, adjustable arms are helpful if one is looking to rock serious aggressive wheels or total control of suspension tuning. There are 2 popular companies known here in the States. VIP owners prefer the Nagisa Auto products and the sideways-sliders like Ikeya Formula. Infact, most professional JDM drift machines recommend Ikeya.
Looking at their years of experience and the amount of proven abuse on race cars, I too am a believer of their products.