It's all i use (hks) and mine's not exactly std, i change them once a year, not that anythings ever wrong i just change them once a year.
Once one of my NGK's caused a miss fire in the skyline and in my pulsar i had 2 tips come off, 2 core's drop out and another fail, simon norris would only let me run HKS S40i's when normal driving and S45i's when using NOS and competing in the pulsar.
So now in the skyline i only use S40i's so far 3 sets in my current skyline and one set in my old skyline for the year i owned it and never had a single problem.
I'm not saying there the best and i'm sure plenty will say NGK's are brilliant and some might even say they've had probs with HKS, its your choice, but personally i wouldn't use anything but HKS or Greddy plugs.
To be fair often the more std cars with just exhaust and induction kit over fuel which could cause probs with sparks, but mine just before it was mapped simon told me a was running rich enough fuel on tick over for 2bar boost flat out and still never had a prob with my sparks?