Sounds promising Sloth: Hard to tell though if it took 18 months for that iffy plug to corrode so badly,
'Keeping an eye on (suspect) things' is our 'owners motto' of course.....
Sadly e-bay is rife with all kinds of suspects/fakes, especially electronics stuff (as many have found out the hard way....
it seems I have become an expert on counterfeit memory cards like that): Markings/Holograms etc are cloned too,
and apparently regardless of bad feedback stating this !
Many of the (genuine) manufacturers have areas of their web sites telling you what to look for (but often 'too late'):
http://www.ngk-sparkplugs.jp/english/techinfo/fake/
(Yes of course the Counterfeiters also read this data in order to improve their fakes...)