Tom's Japan is a very respected tuning facility that work closely with Toyota Japan. In fact the owner of Tom's was once an employee of Toyota. Searching the net the other day, landed me on the Tom's Hong Kong website. Little did I know that Tom's had a branch in HK.
There were many products on the website I have never seen or heard off, including these Tom's BBK. The fronts are 6-pot on 2-piece 334mm rotors while the rears are 4-piston on 324mm. I have to guess if Tom's Japan is willing to put their reputable name on any product it must meet an extreme standard, so from a user point of view, you can rest assure these are top of the line big brakes.
Applications includes: Crown(GRS182/4 UZS186) MARK X(GRX12#) IS250 IS300 IS350(GSE2#) GS300(GRS19# UZS190) ARISTO(JZS16# JZS147) SOAREA(UZZ40) SUPRA(JZA80)
More info at Tom's HK