Capt Steve,

My GT is a distant relative of your F-150 so I will offer my 2 cents. This might be more info that you really want, lol.

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Please ignore the following paragraph and see Post #5, below. It seems that "chip" does not always mean a piggyback computer chip that plugs into the ECU.
end of edit

For $70 and a money-back guarantee, I would go ahead and give a chip a whirl. If your mileage decreases or the power improvement is not there, you can send the chip back and the only cost might be shipping. Advice: clean the contacts on the computer board very well or the chip will not work and your vehicle may not run well. Use a piece of duck tape to secure the chip to the casing because the engine will stall if the chip gets loose.

I only have experience with "flashers". This is a lot more money than the chips that you mention. A flasher is a handheld unit that plugs into the OBDII port and reprograms (flashes) the computer. The stock program is stored in the flasher and the flasher is locked to your vehicle's VIN. You can unlock the flasher and return your computer to stock when you sell your vehicle. A flasher can read and clear trouble codes although most engines do not trip codes very often these days. For Fords, it is hard to beat SCT (Superchips Custom Tuning) at sctflash.com. SCT offers a flasher that comes with 3 tunes that have some adjustability for spark timing, shift points, rear gears/tire diameters, idle speed, etc. The three tunes are typically "87 octane performance, 93 octane performance, and 87 octane mileage" for cars and similar ones for trucks/tow vehicles. Price for such a flasher is about $350. I would argue that these tunes are worth the price since SCT develops tunes for a specific vehicle by using that vehicle (e.g.-a 2006 F-150) running on a dyno. These are well-respected products in the stock to lightly modded car/truck world.

If you want to go whole hog, you can invest in SCT's "ProRacer package" that includes their tuning program called Advantage, their datalogging program (free!) called LiveLink, and a flasher. These allow the user to modify almost all of the aspects of the tune to his/her liking. (I am a ProRacer addict and thoroughly enjoy this hobby.)

Back to your question: I'll see what I can find out about SLR and GForce chips on the other forums where I lurk.

Chris

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/at least she finds me handy.