I got mine yesterday and here is a mini-review after one listen through.
Packaging: This is a Rhino set, which I didn't realize when I ordered it, which is a big plus. It's a normal CD size "box" so it will fit on your shelves. The booklet is top quality-interesting articles and pictures, very comprehensive track info. A nice touch to me is the CD labels look exactly like the old Reprise LP labels I remember fondly. The booklet, as to be expected, glosses over the reason for Parson's untimely death (OD).
Music: Like the Rolling Stone review linked above, the third album (alternative takes) is the real gem. The usual boxset is loaded up with alternate takes or outtakes that are only mildly interesting, and then for one or two listens. Every track on disc three is a fully finished version that can stand on its own. Discs one and two are reissues of the studio albums "GP" and "Greivous Angel" with some extra tracks, mostly interviews, tacked on the end of each. These albums are as great as they were thirty+ years ago, and the extra stuff is actually interesting (except for the instrumental only version of "Return of The Grievous Angel", which maybe you could use for karoke signing). As I was listening to these albums it stuck me how they sounded far more "country" than the usual modern country radio fare.
Production: I was really worried here, because frankly every Gram Parsons LP and previous CD I have heard has sounded like crap. The chief offender to me is the CD reissue of GP and Grievous Angel on one CD, which according to Amazon sells for over $30 now. Stay away from that and buy this set instead. From my first impressions of the box set, they did a great job remastering this finally. Finally I can crank up great tracks like "Brass Buttons" and "$1000 Wedding" without flinching.
Summary: I jumped on this because of the (now dead) great price, but even at the regular price it is a very nice box set. You won't be disappointed here. If the world was fair, Gram Parsons would have been a superstar and the Eagles would have never gone beyond the bar band stage.