Psssssh..
It's all good.
I think you will be fine buying a 6mt. Although to be honest with you I had few problems with transmission grinding but doesn't happen everytime. And it happened around 20,000 miles. Plus I can't make it happen again. I guess there is a small glitch and I bet they alread did some fixing on the newer models.

2003 G35 Coupe 6spd

 

so far so good, bought mine about a month ago.

930 miles.

04 Black G35C 6MT | Premium | Navigation

 

As mentioned before, the TL/CL transmissions aren't that great. I've seen way way more complaints about TL/CL transmissions (as well as other kinds of cars) than G35 transmissions.

 

I've had my 6MT coupe for 6 months/5K miles, no problems. Best car I've ever owned by far. Way far.

 

That was a well stated response. There are a few problems with every car but you will as stated in a few other responses the funny little grin you will have when you walk toward or away from you car almost everytime you drive it.