Tried ChatPDF, AskYourPDF, etc, and gladly settled on this one. Using it not for business, but private. Allows me to load dozens of PDF's, customize the AI agent with custom instructions, and begin chatting with the PDF's. It's GPT4 model is 100% preferred over GPT3.5. The results are world apart better with GPT4. Using it for education. AS a teacher, we deal with lot of knowledge. Let's us quickly find information and present it to the class. And yes, it finds information much better, with more detail then the services mentioned above. Simply because you can choose GPT4, and specify custom instructions, to produce a thorough, detailed and structured output of useful and in-depth information. Recommended for educators dealing with huge amounts of knowledge (even though this is designed to be a customer service tool). TIP: 99% of your success in using this is specifying your own prompt. The default prompt gets 1/10 in context of education, and 8/10 in context of using the AI bot on front-end of your site for customer service. Our custom made prompt (to extract maximum details from PDF's in a structured and logical fashion, including all the analogies, metaphors, and real life examples), gets 9/10 in context of education or self-learning.