A basically very good intellectual biography, if critically dubious at times, but also filled with unnecessary amounts of detail re DFW's personal life, which sadly is probably what is getting this book to sell as well as it seems to be.
We knew enough about DFW's personal life (depression, addiction, major relationships, etc) before this book came out. All I found out from this book were some personal details about DFW that were of interest to me in that I related to them/was to some extent happy to know I shared some interests I wasn't aware I'd shared with DFW: his appreciation of P.G. Wodehouse, his turning to "sad Springsteen and Neil Young" when in bad shape, his writing while listening over and over again to Born in the U.S.A., his taste for M*A*S*H*, The Wire, Twin Peaks, and The X-Files, his well-hidden liking for U2 (oops).
But even these are obviously things I didn't need to know; they are only of mild interest to somebody interested in his writing, and could've been guessed at. Wallace's comic descriptions bear enough resemblance to Wodehouse that I could've guessed that he'd read Wodehouse. His appreciation for Springsteen is predictable given Springsteen's lyrical sincerity and emotional poise in dealing with serious issues re being a human being+American life, etc. etc.
these are only minor details in the book, of course. Unfortunately, much of the book is given to long and detailed accounts of DFW's love life, nearly all of which are totally unnecessary and totally, creepily voyeuristic and hence disrespectful, though some are funny, like the anecdote on his hour-long attempt, in a lobby, to convince Elizabeth Wurtzel that letting him fuck her would constitute a "therapeutic favor." His fiction shows an extensive discomfort with masculinity and its implications re women and the relationship (especially the distance) between men and women. That is enough. Nobody needs to know, especially not in such detail, that DFW was a pussy hound, struggled to keep serious relationships going, but yearned for a serious, adult domestic existence.
All that said, the book does give a good account of Wallace's intellectual development and ideas on what fiction ought to do and how one should live her life. As an intellectual/literary biography, this book is perfectly competent. Max's sketch of Wallace's personal side is the problem; it borders on the distasteful, and ironically will likely have the effect of further romanticizing Wallace and his tragic death, which seems to be the opposite of what Max at least ostensibly wanted, which was to write an account of a very mortal, very troubled, but intensely compassionate man who wrote some good and important fiction and non-fiction.