Its a lil off the jeep side of things, but i bought a set of E3's for my MK4 Jetta back when they were still really new on the market and they worked GREAT (sarcasm), for about 3K miles. It started missing and then throwing codes. A new set of factory NGKs fixed that problem, traded the jetta in with the NGK's still running great after at least 50K miles. No more but OEM for me. just my personal