Probably been said before, but they suck. I did a 100k tuneup on my 2002 LS 3.8L and tried Duralast wires due to temporary insanity (at least I used AC Delco Iridium plugs). After a week or so I noticed a slight gurgling/misfire on acceleration and I thought it was an exhaust leak but I couldn't find it. Slowly got worse over the course of a month. One cold morning I popped the hood and fired her up and heard a distinct electrical crackling, the wires were arcing. So I replaced them with AC Delco 7mm Premiums and she runs like a champ. At least AutoZone gave me a refund on the Durasucks without much fuss. I'll never go cheap on ignition components again.

 

Classic example of "I just did a tune up and know my engine runs rough!!"
thanks for the heads up

 

AC Delco Plugs and wires FTW