No one's talking about this set now that it's out? I guess I'll start.
My very early impressions are that the set is pretty good overall. I've only gotten halfway through disc 1, but those early episodes look nice to my eyes. I find the audio to be fairly low, and I've had to raise the volume on my stereo pretty loud to hear them. Ordinarily that wouldn't be such a big deal, but when the Warner Bros. Television logo hits at the end of each episode, it's so much louder it almost blows me off my couch. If you're going to tack that clip on the end of each episode, why not at least match the audio levels? Not a huge problem, but a little annoying for five seconds at the end of each episode.
As you have probably heard by now, there is an audio issue with one episode, "The Big Bank Robbery", which is missing the music and effects track. Warner's has already started a replacement program, so it's not a life changing problem. For the record, that episode has been screwed up for a while. When MeTV first started carrying The Flintstones, that episode was really strange, it had the audio issue with no music and effects, and the video was really washed out and over exposed looking. Very odd, but I've seen that they've since replaced that one with a fixed version, which I imagine matches up with whatever's on HBOMax. (I may have checked that episode out on Max, but I honestly can't remember at this moment.)
The packaging was a little annoying. I bought mine at Target, and when I gently rocked the box back and forth to see if anything was loose or bouncing around, it sounded perfect. When I opened it at home, multiple discs were actually loose in the box and one hub was broken. I saw some mention of those issues over at the Blu-ray forum as well, so I have to assume it's somewhat widespread. For better or worse, one of the discs that was loose was number 1, which has to be replaced for that audio issue anyway.
Prior to release, a number of people were grousing about how many episodes were being crammed onto a disc, but the half a disc I've watched didn't seem to be suffering any picture issues because of it. Perhaps down the road someone who knows better will point out some failings on that front, but I don't see them. I will say this much though...they've put around 17 episodes on a single disc, while Warner Archive's about-to-be-released Blu for Josie and the Pussycats spreads 16 episodes across TWO discs, so there's probably been SOME potential loss of quality for The Flintstones, whether someone like myself can tell or not. If 17 episodes on a single disc offered no sacrifice or drop in quality whatsoever, WAC wouldn't have used two for Josie. Such is life. (Josie has started shipping from the WB Shop.)
From what I've seen, the episodes DO include the little preview clips at the top of each show. I haven't watched enough to verify that all 166 episodes have 'em though. And someone else pointed out that the Season 1 closing credits are the same for each episode, making the credits information as regards things like who animated any specific episodes useless.
So the set isn't a home run, but it's pretty good overall. Would it have turned out better if WAC had handled the entire thing, without having to pass it off to Warner Home Video? Probably, but we'll never know. With the rise of streaming services and the decline of physical media, this is probably the best (and perhaps LAST) release we're going to get for this content. If you're a Flintstones fan like I am, you'll probably be pretty happy with it.