I first started using these as soon as they came out many years ago. They are a great jack which has improved over the years. The original model had an issue with solderability which was resolved in due course. This was I believe caused by the alloy used in the original manufacturing.
No such problems now, they tin very easily as long as you use a reasonably well powered iron, very small solder tips are not recommended due to the amount of heat required to transfer to the connector when tinning and jointing.
Be sure to place strain relief and clamp on the cable before soldering! not doing so can lead to much frustration and the use of bad language!
For most cable sizes (such as normal 6mm guitar cable) break of the small semi circular part at the front of the clamp. This only needs to be in place for very thin cable, but then you already knew that didn't you? :-0