Less yeast vs colder temp

I know that longer fermentation produces better bread, and there seem to be two main methods of slowing the fermentation:

1. Fermenting at a low temp, in the fridge, with a normal amount of yeast or starter

2. Using a much smaller amount of yeast or starter and fermenting at room temp.

I realize there are all sorts of variants of these, but my question is: given an equal length of fermentation time (say 12 hours) using these methods, is there a significant difference in the result with one or the other method?

Thanks

Michael