I don't believe so. HTC Car uses the Sense framework which doesn't exist on the GPE. There are car apps available in the Play Store that have more functionality, just not nearly as good looking, in my opinion. Car Home Ultra is one such example.
None really... I actually like the HTC Car app better than others out there. But, some people really like the extra GPS features like a speedometer. I'm not a fan of that because it means your GPS is always on.
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