1. Question type and difficulty: The quality and difficulty of the five sets of papers in the University of Technology are very high, especially the number three, which is relatively novel and close to the real question. However, Li Lin's simulation paper is relatively moderate in difficulty and pays attention to the application of basic knowledge, which is suitable for candidates at all levels.

2. Applicable object: The five sets of papers in Gonggong University are suitable for candidates who have a certain foundation and pursue high scores, which can help students achieve better results in postgraduate mathematics. Li Lin simulation paper is suitable for most candidates, especially those with weak foundation, and can help students consolidate basic knowledge.

3. Scope and coverage of the topic: The five volumes of the University of Technology cover the main knowledge points of postgraduate mathematics, but they are not as comprehensive as Li Lin's simulation volume. The topic of Li Lin's simulation paper covers the main knowledge points of postgraduate entrance examination mathematics, which can help candidates comprehensively consolidate and improve their mathematics level.