Article is a bit out of date IMO. Best regarded currently are Z1 and SpecialtyZ. AshSpec, you don't know when you'll get your product or hear from him. JWT is what most of the chips are based off of. Their prices are a bit high IMO.
I've never heard of the chip you're referencing. I'm assuming its something off of eBay. AVOID.
You'll also need to have your ECU socketed, read up. If that "chip" you referenced doesn't require socketing AVOID AVOID AVOID AVOID, it's likely just a resistor that changes the MAF readings which is a cheap and dangerous way to do it.
Edit: Got unlazy and googled that chip.
http://www.gforcechips.com/nissan300zx.aspx I would avoid like the devil. That's not a chip. It just modifies your air flow readings. These are dangerous for any car.