Photos of the three toys I bought from the Toymate store...

The packaging.
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Close-up of the heads.

Robot modes out of packaging.
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The included Igniter Engines are all the same shape/size, but are uniquely sculpted, with different engine-esque parts.
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Vehicle modes.
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With the Igniters plugged in.
They give the vehicle modes a motorised feature, as the Igniter is pushed through to have it's wheel touching the surface - pushing on the grey top tab, has the vehicle rocket off forwards.

Not the prettiest looking gimmick, but the Igniters are interchangable, and other non-vehicle gimmicks will probably be more affecting (less intrusive to the look of the toy's alt-mode or robot-mode).

The gaps without the Igniters.
You can open up the panels before plugging in the Igniter... or push it through, forcing open the panels.
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