To clear up, when I refer to Penetrene, I tend to be reffereing to the Penetrating Oil.
WD-40 can be substituted, but I have never found it near as effective, and for the above purpose (providing lubrication and rinsing during abrasive cleaning) I find WD-40 does not give near as nice a finnish, nor does it provide equivalent oiling to the damaged plastic during cleaning, which increases the risk of permanent damage.
