A lot of people don't like the direction they took once Gurrewitz left, starting with The Grey Race, I believe, up until Process of Belief, so you're not alone there. I honestly love No Substance, and some of the New America stuff is my favorite, but that's just me.
Honestly, pretty much all of their full albums are easily found on Youtube. I'd say of the newest ones, The Empire Strikes First and Process of Belief are the best bets. I like all of their stuff for one reason or another, but overall I'd say Empire Strikes First is your safest bet as a fan of their old stuff. Not a guarantee, but that seems to be the consensus, generally.
My personal favorite from them is No Control, if that gives you a sense of my taste.