This is a pretty decent product, but it's not really all that compatible with standard Mongoose Traveller. This is unfortunate, as the author has assumed that people will adopt his rather extensive house rules used in this product. I think it would be better if the book was modified using a consistent set of rules (either Vehicle Design System or Starships) rather than pulling information from both. Also, the recently released High Guard Errata should be incorporated into this book, which will require adjustment to the Hull/Structure of virtually all the mechs here.
The unique weapon statistics also present an interesting problem. They are completely incompatible with High Guard and the Central Supply Catalog. There are similar weapons listed in the CSC (which is not, to my knowledge Open Game Content) that become hundreds of times more powerful in this product. Similarly, the weapons created for this product are grossly out of scale with High Guard and the Core Book starship weapons.
If the author was able to correct these issues, it would be worth 4, or even 5 stars.
As a disclaimer, it may be that the author is not allowed to use the Vehicle Design System to create published designs. If so, that is a shame, and something that Mongoose ought to remedy by making the products of its design systems OGL-compliant.