over all it is a much easier design to bleed and better manages air pocket and overflow prevention.

Mine is a march 2012 build Australian spec with factory oil cooler and it has the early style tank with the plastic cap ?.I've removed my oem oil cooler and have not noticed any problems with cooling.

Mine to is an early 2012 Australian build with exactly the same setup as you describe on yours. I have not removed the oem oil cooler and have added an after market oil cooler with no issues. I don't use a thermostatic plate with the oil filter as I like the idea of the oem cooler helping to actually warm the oil up a bit when everythings cold, so my oil isn't too cool for too long in cold weather, as I don't use a "block off" plate on my after market oil cooler in the cooler weather.

I’ve just looked at 370z’s on car sales.com and it would seem that all Oz Zeds have the plastic cap on the expansion tank. I removed the oem oil cooler as per fast intentions recommendations and I use a thermostatic plate as here in Victoria it gets pretty cold in winter . Last week with ambient temperatures of 35 celcius it took 10 minutes to get oil temps to 82 celcius and and after 30 minutes driving it peaked at 85c which was a little too cool imho. I made a plate and blocked off a third of the cooler and tested it again and this time it settled at 88c when cruising and peaked at 95 after a few hard runs through the gears, this was with ambient temps of 37c.