I'm pretty satisfied with the subscription as it's a great time-saver, in 15mins I either find out that:
- the book is not worth spending hours of actual reading
- I enjoy the summary and it makes me want to read the whole book
- or I like the summary, copy the highlights into personal notes, and carry on
Real people are both reading and summarizing the books, so it's much higher quality than the automatic shorteners.
And even without trendy 'blinkist' I used to take a similar approach by first reading some prepatory materials before investing time to read the book. Listening to an audiobook is just another way for me to complement but no replacement.
I would not say this is fool proof.
You will never be able to get the "key takeaways" of every book by reading some summary. Sometimes the key takeway might be the way a book is written, how something is repeated while other things are left out that are most valuable.
Likewise quotes that once meant nothing to you, you will only understand after studying material by the other in depth, etc.
just some thoughts.