Good, but not overly so. There are a few instances where the main character (MC) goes slightly out of character, but it’s still manageable.
When the plot involves the rebellious Kyubi and the Ryuchi Cave, the MC tends to act out of character, which can be quite annoying. However, if you can skip these parts, it’s still fine.
The MC is smart and has a bit of a humorous side. At the beginning of the novel, you might find the system frustrating, but by the end, you’ll understand why the MC harbors such intense feelings towards it. There’s no romance, no harems, or any other clichés, and I personally appreciate that (since I dislike romance in fanfics). The MC isn’t fond of killing, which could be seen as either a drawback or an advantage, depending on your preferences. If you enjoy Naruto fanfics with a spy MC or dual identities, you might really like this one.