When you have multiple PST files to convert, processing each file separately can take a lot of time, especially when the files contain years of emails and attachments. It is better to use a tool that supports batch processing and lets you select the required folders before conversion.
I came across SysInfo PST Converter, which can process multiple PST/OST files and convert mailbox data into different formats. It also provides options to select specific folders, preview mailbox data, handle attachments, and maintain the existing folder structure.
One thing I found useful is that you can choose the required output format based on where you need to use the data. This makes it easier to handle PST data for migration, backup, or archival purposes.