stating obvious There is no lock that is undefeatable. I had an Abus Granit X-Plus d-lock (£50) - one of the very highest rated on the market - and came out of my house one morning to find it in pieces & the bike gone. It had been cut through like the proverbial knife through butter. The bike was locked up in the front garden directly beneath our bedroom, so whoever did it was very quick and quiet. So it's all relative.
stating obvious There is no lock that is undefeatable. I had an Abus Granit X-Plus d-lock (£50) - one of the very highest rated on the market - and came out of my house one morning to find it in pieces & the bike gone. It had been cut through like the proverbial knife through butter. The bike was locked up in the front garden directly beneath our bedroom, so whoever did it was very quick and quiet. So it's all relative.