The differences are price and horsepower only. M35 is rated at 275 horsepower and the M45 is rated at 330 horsepower. Resale value is currently stronger on an M35 as well. I recommend the M35 it is more than enough speed and you will save thousands of dollars. I can help you find new and used if you need help. In fact through Infiniti dealersw only you can get a preowned vehicle in the years 2006 and 2007 preowned with a certification covering 6 years 100,00 miles . I am an authorized dealer. Dave Mulgrew @ 951-324-8282 ext 236 or dwmulgrew@aol.com
M45 4.5L V8 - 32 valve 325HP / 336TQ
* Titanium Intake & Exhaust Valves
* Variable Flow Induction System - Optimizes airflow for low and high speed operation.
* Is a little heavier than the M35
They are both fantastic cars. Lots of luxury and performance. Shoot me a PM if you have any specific questions I might be able to help you out with.