I have a 2008 LS460L with Touring package. I just changed my brake pads and rotors. I put on PosiQuiet Ceramic Pads and cross drilled rotors. They work great. a loud squeal developed and I ended up putting on CRC Disc Brake Quiet with the OE shims and also using CRC DeSqueal on the rotors. I also used CRC Synthetic grease for the pins.

My LExus service technician told me the caliper bolts are "stretch" bolts and need to be replaced everytime they are removed. My local dealer in Mission Viejo, CA wanted $5.95 each. I went on line and found Lexus of South Atlanta for significantly less:

front - PN - 9010514180, price - $3.09, torque - 100 lb ft
rear - PN - 91552L1245, price - $1.76, torque - 63 lb ft
you should use a thread lock on the bolts also.
hope this helps.