Recommended Spark Plug for ITR

[ice2004]

Im thinking of replacing my spark plugs and have come into three options:

NGK IRIDIUM IX SPARK PLUGS FOR HONDA heat 7

Platinum Spark Plugs NGK VX heat range7

HKS S-Series Super Fire Racing Spark Plugs 3 models:
S40 Heat 8
S40i Heat 8
S45 Heat 9 ($2 Extra)

Im not sure which one to choose and which one will perform better as this is my first time to replace the plugs on the ITR

The only mods on the car is header and cai and LSD
Btw its a JDM ITR

http://www.trademe.co.nz/Browse/List...x?id=138797864

http://www.trademe.co.nz/Browse/List...x?id=138819587

http://www.trademe.co.nz/Browse/List...x?id=139375322

Can someone direct me to the right option and why should I choose that option as I want to get better performance on my ITR

Heres a picture of my engine bay:

[Bbasso]

Stock motor = stock plugs.

[ice2004]

Ok currently I have NGK R PFR7G-11 on the car will give the NGK iridiums ix a try and might be different. I heard that spark plugs have lot of effect on the cars performance