Tango, may be I've accustomed to my previous wheels which were 16" with 205 thread. Now with 18" 225 front and 235 rear, and with the full tank of gas, braking seen a bit loose. The rolling radius of the 16"/55/205 is actually smaller than the 18"/40/225 and may be that caused the difference. The brake rotor of the IS350 is 330mm diameter while ours is 290mm. I think they should give better braking power at high speed under load. Besides, the price seems quite reasonable. I am going to have them installed next week so will let you know more by then.
TK