They are almost the same, except the storyline of Sud Sai Pan is longer with more detail, which makes it better in my opinion.
The male lead is in both in love with the lookalike of the female lead. The lookalike has left him and when he meets the female lead he thinks it's her. The ML's and FL's are rich. They get married while the ML still thinks the FL is his ex-lover. The lookalike comes back causing trouble. The ML and FL fall in love.
Also: hot forced kisses in both.
The male lead is in both in love with the lookalike of the female lead. The lookalike has left him and when he meets the female lead he thinks it's her. The ML's and FL's are rich. They get married while the ML still thinks the FL is his ex-lover. The lookalike comes back causing trouble. The ML and FL fall in love.
Also: hot forced kisses in both.