Well, we had a new gate fitted by a tradesman last week and I've just swapped the padlock with one of the Abus ones i've been unable to open yet so I can play with the one he left. Took all of about 10 seconds to open....
The padlock is marked up with "Merchant" on a red plastic band and looks like it's built up of lots of plates of steel. It has "2 1/2 64mm" on the bottom. I can rake it open in about 3 seconds and pick it in about 10-20 so a little more practice still needed.