anua niacin dark spot serum or numbuzin 5 vita C serum?

right now i currently use the numbuzin 5 serum and i love it 🙏🏼it works great and i think it did fade my scars fairly quickly. but however they’re still some scarring and i feel like it’s not going away as fast as said, and when i saw the anua results now i’m thinking about getting that one too… would they work in combo together? which ones do you guys love most? :)