Today I suggest you to get SysInspire NSF to PST converter software. This tool has a demo version that can allow users to convert 25 items from each folder. It has a technical support all users can get help by mail or live chat. It show the preview of NSF file. It has a PST splitting option users can split PST file into small sizes. It convert NSF file into multiple file format such as NSF to PST, EML, EMLX, Office 365, Yahoo Mail, Gmail, MSG, MBOX, Zimbra-tgz.etc. It has a 15+ file format for conversion. It show the preview of NSF file before conversion.
If you are finding the tool of taking a backup of IBM Notes NSF files then I suggest you use the eSoftTools NSF to PST Converter Software. This software has the capability to convert IBM Notes NSF files into different formats and after the conversion, you have a backup of your NSF files in your system. It can convert NSF files into multiple formats such as EML, EMLX, MSG, PST, MBOX, CSV, VCS, and many other formats. You can download it from the official website of eSoftTools.