I even tried googling for it, but couldn't find any articles referencing both Guantanamo and casio watches, aside from the general ones talking about the whole phenomenon of Al-Quaeda preferring those watches or pieces talking about incidents where the watch was actually used as an IED component.
By any chance are you Arab? If so, then I can see why that might sting (and why the others were, unfortunately, taking the tack). If you're not though, then meh, easy to dismiss.