In your scenario, you would have pretty much the same strand hair features in both programs.

If you are on a 64-bit system, I'd go for Pro 2012 over Poser 10 because with both editions you would have more time-saving features and better performance.

Without Poser 10, you'd be missing Raytraced Preview, Sub-D, Comic Book mode and the Fitting Room.

However... there are other means to Fit Clothes - utilities here and there, Wardrobe Wizard and using a modeler/re-rigging.  Not easy, but it's there.

Comic Book mode is cool, but you can get similar results in post with a graphics application.  There are also free and pay-for toon shaders at various places.  There's also the sketch designer in both, that you could use as-is or composite in a graphics application.

Sub-D and Raytraced preview are dandy to have but not essential.  Not saying they aren't useful - they are.

Poser Pro, you're getting 64-bit, Background Render, Render Queue, Weight-Map creation, etc.  If I weigh both, I find the Pro features more useful in general.

Just my 2 cents.

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