The best mathematical logic text for beginners would be "Introduction to Mathematical Logic" by Elliott Mendelson. It covers all the fundamental topics in a clear and concise manner, making it easy for beginners to understand.
The most comprehensive mathematical logic text would be "Mathematical Logic" by Joseph R. Shoenfield. It covers a wide range of topics and provides in-depth explanations and proofs.
For self-study, "A Mathematical Introduction to Logic" by Herbert Enderton would be a great choice. It includes exercises and solutions, making it easier for self-learners to practice and check their understanding.
"Mathematical Logic" by George Tourlakis would be the best choice for advanced learners. It covers advanced topics such as model theory and computability theory, making it suitable for graduate level studies.
A good mathematical logic text should have a clear and organized structure, provide thorough explanations and examples, and offer challenging but manageable exercises for practice. It should also have a good balance between theory and applications to real-world problems.