Spark Plugs

Hi, I was wondering what spark plugs other people have been using in there six cylinder cars. I've got a 1962 100 and have been using Champion n5c with no issues at all but in James Taylors book on P4's it says that Rover approved Champion UN12Y which is a protruded nose plug and I was wondering if there was anything to be gained from using protruded nose plugs.
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protruded nose plugs tend to stay cleaner as there tips are further out in the flame front, conversely many race engines revert to retracted electrode plugs as they are less likely to be a cause of pre ignition or detonation in a high compression high rpm engine running on the limits of temperature and octane rating of the fuel.

if you have no issues then your not going to gain anything from changing plugs, but if you have to clean them regularly to keep it running sweet you might be better off using them
Thanks for your reply, that makes complete sense, I'll stick with the n5c's as they seem to suit my car well but it was just something that got me thinking.
Mine had quit a few bad spots when I first got it, I spent 3 years and used a lot of Mig wire to make it solid again. Its been back on the road for just a year now and seems to be going well.
Are you working on your car ?
im supposed to be ,ive collected lots of parts,ive tons of welding to do,i guess it will take a long time,but i enjoy working on them more than driving them