I would avoid these. A golf ball only has to be submerged for a week and it can lose up to 6 yards on average based on a blind test from Golf Digest. X-outs are different - typically just slight imperfections with no effect on playability. Sometimes you can find deals on logo balls as well.
I think you're better off buying brand new balls in the next tier down, like the e6's mentioned above or Titleist NXT's. Also keep an eye out for 3 for 2 deals. Last year Callaway sold 3 dozen HX Tours (their best ball) for the price of 2, and this year Taylormade did the same with the Pentas (also tour-calibur). Averages to under $30/dozen, can't do much better than that.
And LK that's some great playing, congrats on a solid month. I'm knocking on the door but haven't broken through yet. Hit 16 greens at University of Maryland on Friday but only made 2 birdies because the greens were destroyed from aerating - basically unplayable. I've had a 70 and 72 this year in tournaments but am hitting the ball better now than I was then, just can't quite break through. It's all little stuff, so annoying.