Well, you can buy the book separately from their store for something like $5:
http://spartangames.co.uk/shop/index.php?route=product/product&path=62_71&product_id=539
Granted, it is not as convenient as a PDF download, but it is better than buying the box set!
That being said, I have the rulebook, so I can answer any specific questions you might have. In general, the DR,
CR, Mv, and
HP of French ships pretty much match the standard (that is, they don't have the +1 DR of the FSA, or the +1
CR of the EotBS, etc). Their
AP counts tend to be below average; their cruiser only has 4
AP, for example. Their cruisers do have decent long range gunnery, though which is nice.
The French really have a few special things about them, but the most important
IMO are surface skimmers and the Heat lance weapon. Surface skimmers aren't actually flying models, despite having a flight stand. So, while counting as a surface naval model, it can still move over land and intervening models. Heat lances are a neat weapon that has a
AD rating equal to 2x the target's DR. While they are affected by damage, they are also redoubtable, which means that you can still get useful dice from them even when the ship armed with the weapon is heavily damaged.