What are the differences or benefits of running Dr. Scientist pedals at 18V?

With most Dr. Scientist pedals there’s no difference in the sound or operation at 18V, they’ll just be a little louder due to the higher voltage. The Elements is less saturated at higher voltages giving a more clean and open sound.  The BoostBot has more clean boost available at higher voltages.  Higher voltage operation is mainly provided as a convenience.