If you are searching for a tool that is best for viewing MSG files, you can try MacSonik MSG Viewer. This utility allows you to select one or an entire file for viewing MSG files, and it quickly converts many files at once without changing the original data. It is easy and efficient to use. With this tool, you can save MSG files as PST, PDF, etc, and you don’t need extra software to do this. Additionally, this tool is compatible with both Mac OS & Windows OS.

To know more: https://www.macsonik.com/msg-viewer/