Ultimately, you will be the only person capable of deciding whether a particular thing was worth your time or not, and you can only decide that in hindsight, having experienced it. The finest accumulation of the greatest reviews of a work will not make up for the fact that you might glean some valuable tidbit from it that nobody else noticed.
You also have to accept that you simply aren't going to ever be able to know everything about everything that you'd like to; you will have to make choices, pick and choose. Accepting that, would you then rather memorize a pile of summaries and tidbits and factoids, or would you rather take the time to read and consider a complete discourse on a subject?
For example: I'm sitting here thinking about my argument and wondering if I'm really just full of shit, but then I suddenly remembered a bit of "Surely You're Joking, Mr. Feynman", where Feynman talks about some of his experiences in Brazil, and how the teaching at the time resulted in students that had memorized everything but understood very little.
And it strikes me that this relatively recent addiction to summaries is very similar to that kind of Brazilian education.