Sorry to say, but I'm very disapppointed in this product. Coming in at 21 pages should have been my first clue. What I was expecting (and I fault the authors for not posting a decent full-page preview) was a full toolkit. Now, don't get me wrong - what was presented was an excellent series of charts (pretty much the entire book) of the useful base characteristics of vehicles by type and size. Thus, as a bare-bones start, thie product is useful.
What it is not, sadly, is comprehensive.
I'd hoped to see a product with pages devoted to various vehicle add-ons and components, a la Science Fiction Compantion. The fact that this book cites the Companion as a useful book is only indicative of what is truly missing. Also, there are ZERO sample vehicles of any era or type.
Insted, the author advises builders to cite real-world stats where possible, and extrapolate game stats from there. I get not trying to hard-code math conversions - Savage Worlds is not that kind of game, thank God. But some ideas of developing relevant stats would help. Also, advice on when to list nitty gritty aspects. For example, vehicles in 1930s tomb-robbing campaigns set in the jungles of Africa or world-exploring vehicles in science-fication setting need an "endurance" stat related to food and fuel. Such a stat was very useful back in the day of WEG Star Wars d6 system.
For example, I would love to see an author really dig into 1920s cars - which had an amazing breadth of beautiful design - but for which it is damned hard to get even basic stats such as acceleration, top speed, durability, passenger, etc. My 1920s-era players are sick of the Model T, and prefer to drive a Grey Ghost or Dusenberg.
I digress. This guide has the start of an excellent product, but feels less than half-finished. Even the section on non-mechanical vehicles is a simple page of suggestions, with no idea how to mechanically stat such vehicles nor a list of cool ideas. (I'd say see GURPS for some inspiration on biotech vehicles).
All-in-all, a decent product worth $3.00, not $7.00.
EDIT: I'm revising my review a bit. The book does state on it is a "conversion guide, and not a set of rules for building a vehicle from the ground up." Again, that's fine and the confusion could have been solved with a more detailed description and a full-size preview of that page and one of the chart pages. Just to be fair. I hope the author does another vehicles product with all sorts of build items, add-ons, and examples. THAT would be a great idea.