I spontaneously purchased Thief on PS4, I put about 2-3 hours into it. I'm having a lot of fun with it. The stealth is great, the mechanics of the game are really fun. I love that a fairly large portion of the city opens up to you somewhat soon, it gives you some fun side content and exploration between missions. Plus it's cool that you have your own hideout where you can stash your rare stolen goods and put them on display, stash items for later use, etc. It's neat.
If you're a fan of pure stealth, this game is great (3 hours in at least). The combat is fairly horrible, but I think that's intentional. You shouldn't be able to fight more than 1 guard at a time easily since you are a thief, not a fighter. It would take so much away from the stealth if you had no fear of getting caught. As it is, you do not want to get caught cause you can see the death screen quickly unless you run away (which is fun as well).
I recommend it to anyone who want's a real stealth game where stealth is priority and you can't just fight your way through guards, if you enjoy stealing things being a main focus, and if you like semi-open worlds (a big city) to explore/find secrets.