I haven't ever stirred the pot around here but...
I switched back to Nissan's oem MT oil because the Redline MT-85 started causing 2nd gear to grind. No more grinds
I read a lot on the 350z forum about their experiences too. I'm bewildered to say the least, but it seems like some transmissions like the Redline and some like the oem stuff. Its EXACTLY like a Twilight Zone episode