It's nice to have a companion. Very useful for the historical references in particular.

As essentially a summary combined with an extended footnotes, it’s not exactly an easy read. I don’t think it’s supposed to be though, and I found it extremely useful in explaining at least a few of the jokes and important references which flew over my head. Not to mention the benefit of keeping a clean running summary

An essential (and extremely well-researched) companion to Pynchon’s novel.

en excellent companion to the novel. i recommend reading it right alongside it.

Superlative scholarship. You could just keep it handy for those particularly enigmatic bits you simply must have explained, or you could read it--like a book!--front to back, which has the demerit of being a bit of a drag, but it's the only way to invite those unexpected moments of joy and understanding to sneak up on you. It truly excels in the area of onomastics. Next time I'll know about the updated (Internet era!) edition, in which doubtlessly everything n  ISn connected.

Okay I get the point with this one, I wannit off my shelf!
A handy reference guide but nothing more. Doesn't offer much literary analysis or decent chapter summaries in the same way that Elegant Complexity did.
All it really does is serve to show the extensive research that Pynchon did, and it is meticulous at that, but it does not make terribly interesting reading by itself.
All such books begin by saying "Why don't you read a chapter and come back, or read this page then the chapter then this page again" like eugh do people do that??
That I hear, there are interactive versions of Ulysses with pop-up references and the like; books like this are limited in their current form, but if it were available as a collection of hyperlinks that appeared in an interactive GR it would be very useful and illuminating indeed.
I dunno, am I being too lazy, not flicking back between two enormous books clogging up perfectly decent catspace on my lap? (I don't have a cat, but when I do, this kinda thing will be triply impractical!) Yeah, maybe I am, but if it's to my credit, I still use yellow pages, filofaxes and seal all my letters with wax from a melting red obelisk, in which I impress the Robertson family seal and bless with a dab of my finest whale oil.

An utterly invaluable source to keep at hand while tripping your way through Gravity's Rainbow. I still find myself flicking through it from time to time and finding something I had missed in GR.

This was an excellent companion to GR, clarifying both historical contexts and frequently obtuse puns. (I wish I could pull out Pynchon's Hobbesian pun of "Saltieri, Poore, Nash, De Brutus, and Short" in normal conversation, and would have never understood it without Weisenburger. That alone is worth the price of purchase.)

My one scruple, which comes down solely to personal preference, is its self-imposed constraints; in a masochistic endeavor to digest two towering 20th century tomes in quick succession, I had read Ulysses a few months prior and consulted Blamires' Bloomsday Book for similar guidance.

I loved the Bloomsday Book's structure: akin to Cicero, it briefly introduced each episode's parallel to The Odyssey and its broad aesthetic motifs, sensibly paraphrased Joyce's prose into "wideawake language, cutanddry grammar and goahead plot", and continued to elucidate themes, allusions, and interpretations while unraveling its synopsis. Weisenburger's useful guide, conversely, introduced each episode with a vague summary (understandably, so as not to ruin the shock of Pynchon's scatological humor) and then individual line references and corrections, replete with sources and contexts.

Weisenburger accomplished his book's goal with distinction: it was extremely thorough and I could not have imagined reading through GR without his aid; however, I wish he had followed a structure similar to Blamires. All in all, a wonderful aid in your journeys through the Zone! Happy reading, preterite souls.

I found it useful. Skipped around through it after having gone thru GR a good half-dozen or more times.

Reading through it now, without GR to refer to. An interesting way to read a novel, through its references. It's a hell of a lot of scholarly work.

Want to know what the devil Pynchon is talking about? This is an absolutely fantastic reference guide to enrich re-readers and help first-timers deal with the monumental post-modern work of Gravity's Rainbow. First time readers should beware that it may spoil some things before they appear, so only looking up what genuinely befuddles you might be ideal. Re-readers should also note that this work has since been expanded upon elsewhere, such as the Gravity's Rainbow wiki, and shows its age. However the book is a fine buddy to Pynchon's wild opus.

A brilliant accompaniment to Pynchon’s major accomplishment and one of the greater American novels period. Frustrated or bewildered readers should turn here. I’ve read this novel multiple times and taught it a few, and the book is a challenge for sure but this guide is a lifesaver.

I recommend using this reader's guide if you want to read Pynchon's Gravity's Rainbow.

It explains much that is obscure in that remarkable -- and sometimes frustrating -- novel.