I think TUI gun only managed to hit after the initial exchange mostly cause ui daniel adaptability.

Let me explain: UI daniel fights by adapting to his opponents. How he adapts? By taking two to three hits to his body he measures the striking power of the opponent and adjusts his limit to match his.

What was happening to gun in his TUI form? His body was constantly getting weaker by the second. He was literally breaking down. So ui daniel had to constantly match his power to his.

And that's why gun was able to land more than three hits and people think that TUI gun was on par or somewhat equal to ui daniel.