I suppose it could be interesting, but based on your Website, most of those I don't need to see in 3D. Jewelry, for the most part I buy in person ... but if I were to buy a watch online, a straight on view of the face would be fine, maybe a separate view for the clasp.
Same with most of the gadgets you've listed. Maybe it's just me. It just seems a little unnecessary and kitschy than practical.
And to require users to load a plug in is generally a good way to make a lot of people not want to deal with your site.
At least that's my opinion.
I like to beat up pacifists, because they don't fight back ...