Yes. OTMaster provides direct access to individual TrueType/OpenType tables, so it is especially useful for editing aspects of a font once one has progressed from a tool like FontLab to the .ttf or .otf as the source format, e.g. when using VOLT or VTT.

If you run Microsoft's Font Validator test tool on a font after VOLT work, you may find some errors reported, including the maxContext field of the OS/2 table. These can be corrected using OTMaster.

I usually run Font Validator iteratively, so that I can step back and fix any errors resulting from one tool before proceeding to the next, so:

1. FontLat to .otf or ..ttf
2. Font Validator
3. Microsoft's Volt
4. Microsoft's Font Validator
[...possible other tools e.g. VTT for hinting...]
5. OTMaster

VOLT doesn't update the OS/2 table macContext field when it compiles the GSUB and GPOS tables. Font Validator will report this as an error and will also calculate the correct value; then you can use OTMaster to update the OS/2 table.

OTMaster can also be used to do things like add a format 14 cmap table if you have a font with Unicode variant selector codepoints. You can also copy and paste tables between fonts using OTMaster; I find this particularly useful if I have added glyphs to a font directly in VTT and then need to replace the post table with an updated one.

The more tools there are in your workflow, the more useful a tool like OTMaster becomes.