I don’t use the “GSA SEO Indexer” as I use another indexer and a highly optimized list within the Indexer portion of GSA SER. There are more than enough other reasons besides its abilities as an indexer to get the tool. In my opinion, the Indexer sits near the bottom of that list.
If you don’t get any other feedback on your question here you should check out either [BlackHatWorld.com](https://BlackHatWorld.com) or Mathew Woodward’s website. He’s seen as the ‘king’ of GSA SER.