If you are doing a lot of diagnostic work it is a tool that pays for itself with just a use or two. I would think you might need to get two though to cover PCI and PCI-E. If you are looking at working on factory equipment that is computerized you might want to consider an ISA model also. The prices of them seem to be fairly reasonable now making them more accessible.
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Acao Freestar OSS
Master Smuggler, Master Pistoleer, Retired
Cell phones are a lot like religion. Give an arsehole a phone or a god, and they ruin your day.