Great deal for employees, family, enrolled friends. Occasionally. Just be very aware of the loads, because you're space-available, and if your friend that enrolled you is new, his or her seniority is pretty low.
Mine seniority is 25+ years, and I'm usually sitting in a cockpit jumpseat (not an option for you) when I try to go SpaceA. When my wife is coming with me, we buy her a ticket on another airline unless we've got a day or two to get somewhere. It looks good on paper, but that's about all.
Bottom line, most flights are pretty risky. Have your friend check loads up until the day you fly, and have a backup plan unless your travel isn't time-critical.
Good luck
FAB