I promised to give my impression of the book after I had taken a closer look:
First my general verdict:
I can recommend it. It is the only one of the three recent books on the Marshall
that gives a good overview of all important lines on the Marshall and it is well researched.
in the stile of Amazon/Chesscafe valuation I would give it 3.5 stars. 1 star is deducted because it has little original analyses, and half a star is deducted because it annoys me that in lots of lines the game quote or the author of the analysis (not being Vigorito) is missing.
That I substracted only half a star for the missing quotes for games and analysis of others is a sort of average. Personally I would have subtracted a whole star as I think that it should be made clear which lines contain original analysis by Vigorito and which are the intellectual work of others. But I know that part of the chess community wont find this bothering.
To give an impression of the problem. The chapter on the Spassky-variation (main line Marshall) contains 10 pages (page 21 through 30).
*Missing game quotes: 31
*Unattributed analytic lines by others: 13
*Missed important transpositions: 4
*Dubious evaluations and analytic errors: 9
This is more or less typical for all chapters.
I just didnt bother keeping score for all of them

Let me make these points a little:
Missing game quotes:The main line of variation [A]/page 21 was actually played in Tazelaar-Straka. 2007, but is introducted as "I recommend".
The main line of variation [C21]/page 25., was actually played in Elias - Wagenaar. 2004
Unattributed analysisHardings commentary to his own game against Olaffson (page 27) is given without mentioning the source.
One of the main victims is corr.GM Vitomskis, who died last year, and was one of the co-authors of the "Total Marshall CD". A recognition of his original analytic contributions to the Marshall would have been appropriate. But unfortunately in the whole book hardly any of his contributions is properly attributed.
Another "victim" is Blatny who both as a player and an analyst contributed to theory.
There is one notable exception: Nunn's analysis is properly quoted throughout the book. Now this would not have something to do with the fact that Nunn is one of the bosses/editor's in chief of Gambit Pub.
TranspositionsRecognizing these is not one of Vigorito's strong points. In several positions he misses direct transpositions to other variations in the book, instead giving a new variation.
Dubious Evaluations/Analytical errors*The number of clear computational/analytic errors is in general negligible. The only chapter that contains quite a lot of them is the chapter on the pawn push,
as I remarked earlier in this thread.
*There is a number of dubious endgame evaluations where Black is a pawn down, but is in no danger of loosing if he knows what he is doing. The opinion on those is of course a bit personal.
Two examples:
example 1
Metz-Oim, 1988
Vigorito now gives 30...Ra6! following the game score.
But Black has an interesting possibility Vigorito does not mention:
example 1 continued30...Qh1 31.Ke2,Rxe3 32.fxe3,Qxh2+ 33.Kd3,Qg2!

Now take a good look: How is white going to stop the h-pawn?
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example 2
This position was reached in the game corr. Tacke-Kraft. Both players are of corr.master strength (2400+).
Incidentally this is one of the missing game quotations.
In the actual game white decided to repeat the moves and accede a draw.
Vigorito however claims that White is winning and gives 25.Qa5, Rxb2 26.Qd8+,Bf8 27.Ra8 to make his point.
The first question you might ask is: would two very strong corr. players both have missed this simple line?
(that his if you knew the source)If you look at the position a little bit longer,
25.Qa5, h6! will come natural to any strong Marshall player. After Black has disposed of the 8th rank tricks Black's threats on the K-side and the attack on the b-pawn are renewed, and it will prove difficult for white to make progress.
One sample variation:
26.Rab1, Rf6 (26...Rc8 is good as well) 27.Nd2,Rf5 (threatening Qh3-Rh5)