neXus, what are you upgrading from?? That would help us to determine if it will be worth it for you. If you have an AGP graphic tower, then also do the following... Max out the RAM, upgrade the video card to at least the Mac edition Radeon card (if not the 7000 or 8500). Also consider getting an ATA133 controller card and getting a newer, larger hard drive (something in ATA100 or 133). All of that combined will give you a larger boost in performace, along with the processor upgrade.
As for getting the dual upgrade, call Sonnet, see if they anything faster in the works. Pose it as a resolution to a discussion you are having (not that you are looking to buy now). That way, they will be more inclined to be honest with you. Who knows, they might be working on a dual 800MHz upgrade
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