The resizing algorithm set in the photoshop preferences (bicubic, etc) is applied when resizing smart objects. I have found that if I am unhappy with how one algorithm looks, I switch to another, free transform the smart object (but make no sizing adjustment) and hit enter. The object will be rerendered with the newly selected algorithm.

I found the settings, but somehow it's just still not the same. I now do the smart object stuff until it's all settled, than resize to 100%, rasterize and resize back to what I had set.