Honestly, I don't remember. I rarely drive the car at night and as of right now, I must have put maybe 300 miles on the car in the last year?
Besides, when you're driving, you can't see your headlights from the other side.
If I recall correctly, we only have a headlight beam on one side so only one lights up. The reason why it looks like both are lit is because of the led rings inside.
Anyway, I bought all of my lighting stuff from clearcorners.com
It's not cheap but in the event anything ever goes wrong, Mike stands by his products and will make things right (unlike a couple of the new fly by night led taillight vendors that we've seen come through these forums which I won't name). Hopefully the new guys (Bright Light Tech and dreamerstudio) can offer NSX owners another alternative for taillights for those that want them.