I just ordered seeds from Park Seeds. I will let you know how they work out.

I've got mine in the germinating setup, same as the other begonia (and other) seeds--heat mat, humidity dome, grow lights. The pelleted seed hasn't germinated yet, although other unpelleted begonia seed from other sources has germinated just fine.

Okay--my Braveheart germinated today. It took 8 days, whereas my unpelleted seed took 7 days. I doubt that's sufficiently statistically significant a difference to be worth exploring.