
An additional benefit of dry samples is the increased polyphony you gain by Hauptwerk not needing to play lengthy release samples.
I currently own both the dry and wet Skinner organs, and have decided that I much prefer the dry set - the sound is just much more realistic across all playing styles.
It doesn't necessarily follow that dry samples take less memory than wet ones, because the sample set maker may chose to make use of the availeble memory by using multiple loops/attacks/releases per sample.