Boy... interesting to see THIS kind of thread again...
I have had my 05 to the dealer on 3 occasions for this, and they always told me it is normal. The very last time, they changed the fluid to some "new" Acura fluid that has just become available. That made a big difference. It's not perfect, but it's much better.
Right now weather is warmer and I have no issues at all. Even on startup, it's smooth. On cold days, it's definitely notchy. How notchy? I did hear an actual GRIND once. It just isn't happy going 1-2 when cold. I tried different RPM's, rev matching, nothing helped.
My solution was to just go 1-3 and double clutch to reduce the stress on the synchros since skip shifting is an absolute no-no from Acura. If you double clutch, you won't hurt the trans. I let the car warm up fully, then shift 1-2.
The question is, is this a real inherent problem. They also told me at first that my wobbly headlamps were also "normal". Since I brought this issue up on the forum, and since Comtec took his apart, it's very clear that there is a design flaw with a washer that is too thin. So it's normal in that most have it, but not normal because it shouldn't be there.
The tech told me on the headlamps that the problem is that too few NSX owners complain. They are far and few in between anyway, and those that have a problem self-medicate. He said that Honda simply won't be aware of an issue unless more people complain. Be he clearly saw the problem in the headlamps. They ordered a new one for me, and its been good. It's a luck of the draw. Something in some of them is not to spec. I think this same thing may be happening with the trans. Not enough people complaining.
This problem too may never be adressed by Acura if not enough people complain. In a cold climate, it's bad. It's annoying. Like I said... so bad that I have had it grind once or twice. My suggestion to you is to definitely get the fluid changed over (should be under warranty) and DOCUMENT your complaints in case something does go wrong.
One last thing... the foreman at my dealer that has seen a lot of NSX's said that they went into one and replaced parts.. synchros and stuff... but that was to no avail. He didn't recommend getting into mine with such low milage, and I agreed. Anytime your car is taken apart at the dealer, it won't go back together the same way.