Anybody tried them in the LS? Or any other car for that matter? They look... interesting, to say the least.

It has been my experience to stick with OEM, the plug the car was developed with.

There has been some members that have used BOSH or NKG with mixed results.

Well I don't plan on using them. Not in the LS at least. I'll stick with the stock NGK plugs for now. Might upgrade to NGKs Iridium IX plugs later this summer if I decide to do the Accel COP swap.

These look to be the same idea as those splitfire plugs that were heavily marketed just a few years ago and now seem to have disappeared. :p

I saw the E3's on powerblock last weekend and wondered if they'd work in the LS. I didn't know if it would cause any problems and didn't want to be the lab rat for them.

I put them in the aveo when I did the tune up. I did notice fuel increase but it was a 40,000 mile tune up with plugs and upgraded wires. So, kind of a bias answer. would not say the are bad though.

This is what power block claimed - > http://powerblocktv.com/blog/?p=203

So you MIGHT get 1-2 mpg better on the highway... according to powerblock.