First of all, you do need a little bit of knowledge of the fate universe to fully enjoy Redline. But if you've watched any fate anime, then you're most likely chill (Including Kaleid cuz if you watched that then u prolly watched other fate as well). So far only a few chapters have been translated so I will give short review of whether this is worth your time.
Redline is without a doubt going for the darker and gory side of the Holy Grail War, so if you enjoyed F/Z because of it's dark setting and intense + badass + gory fighting then Redline is
for you. But that doesn't mean Redline's story and writing are comparable to F/Z, Redline's story so far is at best a good (7).
Characters are decently written, the mc is pretty bland but with some development can definitely be a great character. The main servant is badass and with incredible art, she's even cooler(cuter). If you have previous knowledge of her then this portrayal of her is something new but very welcoming as well.
Speaking of art, the manga as some of the coolest panels and fight choreography. The gore is also nothing to scoff that, with fingers being cut off and bare bones showing and such. The tension of fights are single-handedly carried by the incredible art.
The manga so far hasn't made me feel it's too edgy which a lot of people seem to complain all the time. If you wanna just see some cool stuff that's also based in the fate universe then definitely don't miss this.