For a 30USD PDF I'd prefer this be self-contained and not require the Traveller sourcebook, but ...
2300AD is easily my favorite Sci-Fi setting. I still have (and still have fond memories of) the 2300AD Boxed set from 1988. Just as I think Mongoose has done an excellent job with Traveller, they've gone and done it again with 2300AD.
[5 of 5 Stars!]