VSE v VPS v PE
VSE (vinyl siloxanether) is the newest impression material and reports to have the advantages of both PE (polyether) and VPS (vinyl polysiloxane or addition silicone).
VSE acceptable Stober 2010 J Pros Dent
VSE better Pandey JDental Medical Sciences 2014
VPS better Schaefer 2013 J Pros Dent
Many of these numbers are so small that they are clinically insignificant. Also important to remember that setting expansion of modern Type IV die stones is designed to match the inherent volume loss of elastomeric impression material. Any mild improvement of accuracy may actually be hurting.