whats better? and will it increase performance? what aspects?

Turbo head engines have turbo plugs which require no shim unlike standard plugs. An article years ago mentioned that the difference was about 3,000rpm at a certain part of the engines powerband. However, if out of tune it would perform as fast as a correctly tuned standard plug. I ran a turbo head with turbo plug on my RB V12 3 Port Rody and I did notice a slight difference. For the price to switch it isn't worth it. For me it was a test. Most .12 race engines use turbo plugs anyway.

Switching to normal plugs is an idea which has came up by several dutch drivers. The Novarossi Turbo plugs are crap, there are no GRP's plugs to find as the same with the praisen Sirio plugs and the OS are to expensive. The choice is very thin and the hope is based on the restarted production of GRP.

With the Normal plugs there is a very wide choice with top brands like Enya and they are cheaper than turbo.

I have had really good luck with O'Donnell Turbo plugs. 97T ,99T. They seem to be very hard to kill, and are pretty in-expensive. Anybody else have experience with them?