This review is partially in response to one written by Jeffrey D. Sherwood. Jeffrey wrote that he was expecting the art style to be similar to that of the GITS anime series and films. However, there are some key differences between how anime cel art and manga art are done. The original manga btw, predate the anime, so one could argue that it would have been nice if the anime replicated Shirow's unique and captivating style.
Jeffrey refers to the art as "rough". It is important to note that Shirow has a very kinetic style, and uses heavier ink lines than many more recent manga. His color pages (atleast his older work), used a variety of oils, inks, photocopy scans and other methods to produce color. His newer work in Ghost in the Shell 2 uses amazingly well done CGI.
On the note of the story focusing on Togusa and Azuma, Shirow will often use interim or stand alone issues to further flesh out characters that play and intergral role in the overall series but don't get the spotlight. This is quite refreshing, but works mostly because these are actually quite interesting characters in their own right.
GITS 1.5 is another great addition to the series. And even if you were introduced to the series through the anime, if you can appreciate the subtle differences between the anime and manga art story telling styles, there is no reason not to enjoy this book just as much as say the GITS:SAC series.