I've done quite a bit of research and for a bolt on replacement that seems to really perform, I'm ordering the frozen rotors and pads. 41K miles and the high speed shimmy is now there . . . (Y34, BTW)
http://www.frozenrotors.com
A LOT of race teams use these and the rotors last a full season or longer. That's a HUGE difference over stock. So, a bolt on drilled/slotted rotor with reduced heat build up, shorter stopping distances and a lifetime warranty -- for about what the dealer wants for an OEM job. Also, the rotors wear from 200% to 400% better than OEM and pads last much longer too. A Win/Win in my book.
Lot's of aerospace research has been done over the years using cryogenics (typically utilizing liquid nitrogen to cool metals to hundreds of degrees below zero -- this is NOT just sticking your rotors in the freezer at home) to harden and stregthen alloys and steels. The technique is now perfected and these rotors are one of the results. I'd highly recommend you check this alternative out before spending 2 grand on the G37 conversion. BONUS -- found a coupon code worth 15% on your order so if you go online and order, use CODE FR1394 and that should get you 15% off the total - no guarantees but it worked for me.
here's an excerpt from Wikipedia -- The field of cryogenics advanced during World War II when scientists found that metals frozen to low temperatures showed more resistance to wear. Based on this theory of cryogenic hardening, the commercial cryogenic processing industry was founded in 1966 by Ed Busch. With a background in the heat treating industry, Busch founded a company in Detroit called CryoTech in 1966. Though CryoTech later merged with 300 Below to create the largest and oldest commercial cryogenics company in the world, they originally experimented with the possibility of increasing the life of metal tools to anywhere between 200%-400% of the original life expectancy using cryogenic tempering instead of heat treating. This evolved in the late 1990s into the treatment of other parts (that did more than just increase the life of a product) such as amplifier valves (improved sound quality), baseball bats (greater sweet spot), golf clubs (greater sweet spot), racing engines (greater performance under stress), firearms (less warping after continuous shooting), knives, razor blades, brake rotors and even pantyhose. The theory was based on how heat-treating metal works (the temperatures are lowered to room temperature from a high degree causing certain strength increases in the molecular structure to occur) and supposed that continuing the descent would allow for further strength increases. Using liquid nitrogen, CryoTech formulated the first early version of the cryogenic processor. Unfortunately for the newly-born industry, the results were unstable, as components sometimes experienced thermal shock when they were cooled too fast. Some components in early tests even shattered because of the ultra-low temperatures. In the late twentieth century, the field improved significantly with the rise of applied research, which coupled microprocessor based industrial controls to the cryogenic processor in order to create more stable results.