I haven't used it, but based on comments I've seen:

• Users are happy with it.
• But many users that have used multiple AI programs think other services give better results (I don't recall which ones).
• If you can learn some good phrasing to limit results to official tax guidance and IRS pages (and ask for citations), you can save some money and use general AI searches (ChatGPT, etc.) and get as-good or better results.  That is basically what the tax-specific program do; they just automatically add a few phrases to only search within sources for the answers.