I have recorded 60P video with my Nikon D5500 and placed it on a 30P timeline in Vegas Pro 12.

I've set the event properties playback rate to .500 and I disabled the Resample function.

I then dragged the right edge of the 30-second event out to 60 seconds long.

Rendered the file to a 30P format and the footage looks great and is very smooth.

My question is: What's the consensus on choosing what to do with the Resample function if it's a situation with a perfect division of frame rate? Does it matter? Is one choice known to be better than another?
What about a playback rate of .250, what then?

Thanks in advance!