Hi John,
I suppose it could be defeated, but it would take a LOT more work than most thieves are prepared to deal with... I've used one for years on my Honda 2 HP - man, talk about overkill, especially for an engine that very few thieves would bother with, anyway... (grin)
My only complaint about the Stazo, which is a bit surprising for a Dutch-made item of such obvious quality, is that the stainless tends to show a bit of rust rather easily... No big deal, solely cosmetic, doesn't affect the workings, just requires a regular polishing to keep it from getting out of hand...
Other than that, highly recommended, you can't go wrong with the deal John H is offering you... Just don't ever lose the keys, or the record of the key code, I pity the cruiser who ever manages to do that... (grin)
best regards,
Jon