... if you expect it to be like the BU, you'll be disappointed. I was very disappointed, I love the BU, and I've read and watched everything that is available, so I've been very excited about this series for years now... unfortunately, the series do not follow the original story. They take things from here and there, but they change a lot of things and skip/add things. Some things they add felt unnecessary.

I was very disappointed by Kim Jooan's (Taehyung) and his father's relationship, and the relationship they had.
But I was very satisfied with both Park Haru (Jimin) and Jeon Jeha's (Jungkook's) families and those story lines. I was on the other hand disappointed by the reason Cein was expelled, in the original BU, he ended up in trouble to protect Jeha (Jungkook), but they went a different route in this series.

I also felt like it was rushed, and the way the boys bonded felt equally as rushed, as if they bonded just because they had to for the sake of the plot. I never got that impression from the BU. The only ones I felt had somewhat of a chance to bond were Dogeon and Jooan (Namjoon & Taehyung), and Hwan and Cein (Jin & Yoongi). I loved those scenes with Dogeon and Jooan in Episode 1 and the scene with Hwan and Cein in Episode 2.

Episode 1 and 2 were both great episodes, because they focused a lot on the boys friendship, and I feel like we needed more of that before we introduced all the boys' struggles. Right now I feel like they more often faught than actually had fun together.

About Haru and Hosu (Jimin and Hoseok), the way they went with convincing the audience they are great friends was "all tell not show". They kept telling the audience what great friends they are instead of really showing us, because most of the time Haru tried to avoid Hosu.

So was the series bad? No, not at all, I did enjoy it if I tried to not compare it with the BU. But was it great? No, it wasn't great either. We need more happy scenes with them actually having fun together... we espeically need Hwan (Jin) to have more fun with the boys. I know they tried to convince the audience that Hwan cared about the others but I ended up wondering why he cared so much.
And the way they include the timeloop's twist so late, it made things yet again feel so rushed.

And there wasn't a satisfying ending, so we'll have to keep our fingers crossed for a season 2.

I would recommend it, it's worth watching, the actors really helped making the experience better, they are great! But nothing I would rewatch myself.