Where is the Moderators when you need them! LOL It really depends on your mods and how far out your tune really is. For a NA combo I would go with a chip tuned for your car on the dyno. I'm not a real big fan of the mailorder chip. One chip may make 20hp on one car and 10 on another. Get one dialed in for your car.
I agree with the above. Dynotuning will make a big difference. Mail order tunes are on the safe side. Not that dyno tuning is not safe. It's just your chip can be tuned on the dyno to your own vehicle's characterics and limitations.
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