Based upon my experience and what others have said in this forum your GE speaker cables will sound good right out of the box.
When you install them, set the speaker cables up exactly the way you want them and then don't move them around or it will degrade the sound for a while and require another short break-in period.
I also suggest all speaker cables and power cords be elevated off the floor sitting on top of some type of riser for best performance.
Total break in time can run anywhere between 50 - 150 hours for full break in, however, I'm sure you will be impressed as soon as you install them in your system.
My speaker cables that I purchased this past summer have directional arrows, but if the speaker cables you receive don't have direction arrows just install them and use a piece of tape (or something) to indicate what direction you are going to run them. This will prevent any confussion in the future if you need to reinstall them.
Give us a report on your findings here when you receive them.
Best regards...