Back when I had my headers installed, I had the ignition wires replaced with the MSD 8.5 wires. Also had the plugs replaced with the E3 brand, based on reviews I read. However, when I got the STS kit, it came with a colder set of NGK plugs that replaced the E3s. I liked the design of the E3 plugs and the reviews I read seemed all positive, so maybe some day I will get a colder set of them and put them in.
As for the wires, I guess they are so short that there really isn't going to be that much difference from one brand to the next. As long as enough spark gets to the plug to have complete ignition, there really isn't anything more you can do to improve things. If the ignition for each cylinder reliably fires each cylinder when it is supposed to fire, and combustion is as complete as it can be, there is nothing more to improve upon with those components.
The E3 plug design just seemed to me to make sense for more efficient combustion in the cylinder. As to whether or not it actually did that, well it beats me. Unless you have ignition failures, I doubt there is really much you could determine in seat of the pants improvements.
As for ignition wires, a solid copper or silver wire with an insulator wrapped around it is the best you can do. However, with all the electronics under the hood, RF suppressive wires are probably a good idea to keep those radio frequencies from screwing up something with interference. I can remember in the old days putting solid copper core wires on my GTO and screwing up radios on cars all around me...
![Hehehe](images/smilies/hehehe.gif)
Not a chance I could listen to mine at all....