Any Experiences with Grip Locks?

I saw this on ebay and was wondering if anybody uses/used one and what the comments are.

Do you think it will be any good?

Pretty pointless as a thief can unbolt the brake lever or slice the brake line with little trouble.

you’re right, probably not worth getting then!

A thief will lift the bike into the back of a van. A pretty useless product really.

So are disc locks pretty useless as well?

Unfortunately yes, but they are better then nothing.