I thought it would be useful to write a review, having purchased this around 5 months ago and used it regularly.
This lock has become more and more stiff with use, and it has now got to the point where every time I lock my bike up I wonder if I'll be able to unlock it ever again. My friends and I all have this lock, as it is a very popular one, and the same thing has happened to them. It seemed fine for the first few months of usage but now when I put the key in, I can turn it to about half way and then it jams, and I really have to jiggle it around (more and more every time, and very vigourously) to actually get the lock undone. Sometimes I can be there for a good 5 minutes trying to get it undone, to the point where I almost give up and walk home! Several of my friends have had to buy new locks because of this problem and I will also be buying a new one.
I am not sure if this has happened due to something we have done to it, but I always cover the keyhole up and I have also tried oiling it, neither of which have seemed to prevent this from happening. This is a shame because the lock looks great and it is very sturdy with a lot of promise.
I hope that this will be helpful to bear in mind, even if you do still decide to buy it. All I'm saying is that I know a lot of people that the same thing has happened to, which doesn't seem like a coincidence.