It's uneven, but I didn't think any of it was awful and some of it is pretty good. The biggest problem is that they're drawing transportation from stories from the '50's that have been endlessly imitated in various media or revisited with more complexity in Dick's novels, and that's a pretty consistent complaint. There is not, however, much consistency on how people rank the episodes. Thoughts on a few of them:
Human Is - This one stars producer Bryan Cranston, who is good in it, and it is the episode that most resembles the story that it's based on. It's too predicable though, and alot of people think it's one of the weaker episodes.
The Commuter - A fair number of people, including critics who wrote grumpy reviews about how the series isn't very good, thought this was one of the best episodes. But honestly I wasn't a huge fan. It was the one episode where I was bothered by how much it strayed from the story. Both versions are about a pocket universe, but the TV version eliminates the stuff about different realities bleeding into each other. But hey, what do expect from Amazon after they made an entire series out of Man in the High Castle that apparently junked that entire aspect of the book (which is why I'm not going to bother with it).
Kill All Others (based, not very closely, on The Hanging Stranger) - This is one of the best loved episodes but I wasn't a huge fan. I enjoyed Mel Rodriguez but the political commentary was too ham-fisted. The story probably would have felt played out by season 5 of The Twilight Zone.
Safe and Sound (supposedly based on Foster, You're Dead, but it has almost nothing to do with it) - Alot of people criticized this anti-smart phone parable for being too heavy handed but the combination of PKD paranoia and highschool angst works IMHO. Maura Tierney, who I'm not familiar with, looks like Steven Tyler in this episode.
Crazy Diamond - This is the most disliked episode but it has its fans, and they include me. It's weird and offbeat and has the most distinctive production design, and it stars Steve Buscemi. It's funny that while it has little to do with the story (Sales Pitch) there's a part where a character briefly describes the plot of Sales Pitch as a dream she'd had the night before. And yes, the title is a Pink Floyd reference. Robin Hitchcock and Graham Coxon's cover of Syd Barratt's "Octopus" is featured prominently.
Of the rest:
Impossible Planet, The Hood Maker, & The Father Thing are meh.
Autofac and Real Life are good. Although the later is supposed to be based on Exhibit Piece, which it has nothing to do with, when it owes more to We Can Remember It For You Wholesale (the inspiration for Total Recall.