Do Like:
Bill Croft (MoTeC and EMS tech advisor and beta tester) keeps telling me to use magnacor. Evidently he did some dyno testing for MoTeC trying different types of leads on the NA Lotus Targa Tas cars a couple of years back (he's got a dyno in his shed in his back yard!) and at peak revs they made a substantial difference, at low-mid not that much. Not that I cant remember exactly what it was, but it was something like 2 or 3 percent over others. They were running a full motec CDI ignition.
We ran them on a 16v 4age and got 92rwhp from a bog stock motor, only did ign, ECU and some dyno time to tune so something worked well!
Magnacor are pretty exe though...
Do Like:
Stock - why not, theyre already there, the right length and reliable!
Dont Like:
Eagle - poor quality for the expense.