Here's some help:
1. Try to avoid platinum plugs, it will mess up ignition performance. Double Platinum plugs are dangerous too because the platinum chip can separate from the plug and a piece of platinum falling into the combustion chamber could a huge huge disaster.
2. A plug with a short ground electrode is more important than a colder temperature plug and this is why - Temp increases so severely that a longer ground electrode will take longer to conduct the heat away from the tip. This could cause detonation, which you don't want.
3. Try to use a non resistor or iridium plug if possible with the coldest heat range so that the plug can be returned to a safe operating temperature as quickly as possible after the nitrous burst.
4. Also straying from your factory suggested plugs will decrease low load/ low rpm performance. So you will want a set of plugs for daily driving and a set of plugs described above for extreme use. This is required if you listen to anything here, please listen to that.
Hope that helps..