Koji interviews your customer with AI too. StoryVoice is the one that sends the story back to her.

Start with the concession, because it is the reason this comparison is worth reading. Koji actually conducts the interview. Almost nothing else in this category does: the rest hand you a question form, or ask you to turn up with a recording you already made. Koji runs AI-moderated voice and text sessions with up to three probing follow-ups per question, and it is the only other tool we have found that does the conversation itself. If you have been told that every AI case study tool is a text box with a prompt in it, Koji is the exception, and so are we.

The difference is what each product is built to hand you afterwards. Koji is an AI-native customer research platform. It themes transcripts automatically and produces a stakeholder-ready research report, and customer testimonials and case studies sit alongside that as a documented use case. Notice what a research report is optimised for: the pattern across many conversations, written for an audience inside your own company. A case study is optimised for the opposite. One named person, one story, written for a buyer who has never met either of you.

That difference shows up hardest at the moment the story is finished. Koji's own documentation tells marketers to handle approval themselves. In their words: “Send the draft back for approval. Even with consent, send the customer the draft case study before publishing.” That is good advice and we would give it too. It is also a step somebody has to remember, over email, every single time, with no link for her to open and no way for her to approve, ask for a change, or fix a number from inside the product. The intention is rarely what fails. The twentieth time is.

StoryVoice makes that step part of the product. Your customer opens her own link and can do three things: approve it, ask for a change in her own words, or edit it herself, the copy and the numbers on the cards alike. The review her legal or comms team wants, which is the thing that actually stalls B2B case studies for weeks, happens on that page instead of inside a thread nobody can reconstruct later. The change history names people rather than saying “you”, so she and the marketer read exactly the same account of who changed what.

Koji's quote tracing deserves credit, because verbatim tracing back to the source is more than most tools attempt. The question is who is looking at it. Koji's tracing lives in the internal research dashboard, where your team reads it, and your team already believes the story. StoryVoice points the same idea at the person it changes something for. On the approval screen, every metric card opens the passage from the recording it was read from. A customer who said “onboarding took six weeks, now it's about nine days” sees the headline “78% faster onboarding” sitting on top of that exact sentence, and she is the only person alive who can tell you whether that is a fair reading of what she meant. If she or the marketer changes a figure, the card says so and keeps the passage, so a number never keeps a claim it has lost.

The last difference is what the same conversation is worth. Koji's output is built to be read by your team. StoryVoice's is built to be read by your buyer, so one interview returns the publish-ready story plus a LinkedIn post, an X post, a pull quote and a sales email, all in the customer's own vocabulary rather than yours.