Top Three Special Promo Editions...

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EDIT...Actually I have found more than three...Now 6 Below:

Other than the "Chrome Line Regulars" And 'Stealth Editions" etc, here are my top three choices of "Rare Special Promo Editions". If you are starting GT5 again or simply can't find these cars you can message me for further info...

Chevrolet Camaro SS "Edge Special"-Schick Edge Razor Promo...

Jaguar XJ13 Race Car Chrome Line-Facebook GT5 Mini Game Promo...

Toyota 2010 Joey Logano #20 GameStop CAMRY (Fantasy)-GameStop Promo...

 

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Oh... I'll also give this one a honorable mention cause it's "Not" classified as a Stealth, but was a (Academy Special) promo...

Nissan GT-R SpecV (GT Academy Special)-GT Academy Promo...

 

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There are actually two more...
The Toyota FT-86II concept '11 as in the Complete Pack 1 Promo.
The KART 125 SPL as in the DSL Pack Promo.