So not all too long ago I was sitting at my local mechanic getting new distributor cap and rotor put on the Suburban. I need to get the wires changed soon and figured I may as well get the plugs done as well. I asked Mike (mechanic shop owner guy) about the Pulstar plugs. He said he'd never used them and didn't know much about them. I told him the hype they have on their ads about increase in horsepower, better fuel burn, etc etc. He then said (paraphrasing) 'here's the thing... when it comes to igniting fuel I don't see how you can improve all too much on a current system set up. Fuel (gas) ignites at a certain temperature. Once that spark hits the fuel/air mixture it's up to the actual fuel/air mixture to take over from there. It ignites. That's all the plugs do. So if you have a plug that sparks at 1 billion degrees, it won't do any more good than just the initial igniting of the fuel...' blah blah blah... basically what he was saying was that a good plug is a good plug that brings a good consistent spark to the entire system. He wasn't sure on how much more effective the $20 plugs would be from the $5 ones. Soooo... what does anyone/everyone think? What makes a good plug..?.. why not stick with stock AC Delco? What, in your mind, makes Plug A better than Plug B? Have you seen the Pulstar plugs and/or have you used them before? What's your general perception? Did you honestly gain any MPGs using the $20 plugs?