I've been researching this a bit sense i have just purchased a Weller SP40us Soldering iron that apparently from my research seems to have a weakness in the tip area and not surprisingly because on the package it said "Made in Mexico".
So apparently one should stay away from the newer "red" wellers.
My research has brought me to the conclusion that, if you can find them and afford them, Tungsten Copper (Elkonite) electrodes in rod form seem to be the best option when it comes to heat transfer and corrosion resistance.

Mod note: Question was attached to an old thread. Now you have your own.
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OldNoob, it's not entirely clear to me what you mean by "weakness in the tip area" of your soldering iron. Do you mean that it gets soft when heated? Even if it does, are you pressing to hard with it? This article has some pretty good advice about choosing and using a soldering tip.
From pictures, it seems to me that the SP40US has a pretty wide soldering tip, and that may not be what you need for close in PCB work. In my experience, use a wide tip when you have to solder something that can absorb a lot of heat before its temperature rises enough to melt solder. A car battery cable, for example. Use small tips for small electronics work.
All that said, if you can find tungsten copper alloys machined to fit your soldering iron, I think it would likely improve its performance.