Dead easy to fit, and cheap to buy for the pushbike version, it's a security "must have".

I've heard a few stories of people getting their bikes back because the datatag made it possible to track the owner's identity by the police.

It is also an effective deterrent - the original owner can always be tracked my the electronic tag or the remove-proof stickers, and thieves know this. A guy I know through diving used to steal bikes in his younger days (and was properly detained at her majesty's pleasure for it!) - he told me that if he saw a bike was as secure as mine, he wouldn't even bother, just move on to easier pickings - Zefal anti-theft skewers, Datatag, and a quality padlock.

Why would anyone with a valuable bike choose not to do it?