I asked this very question over at the Cruiser Forums, I'll see if I can find the thread, but the short answer is "Ruffwear." Because so many endorsed this brand of dog life jackets, I bought one and very happy with it. The jackets are more expensive than others but you will see they are well made, strong, excellent fitting, and cover a lot of the body.
I just watched this video, make sure to test fit it, its easy to get it wrong with these jackets.
We now also have a Ruffwear vest which my dog wears multiple times daily.
My thread at the Cruiser forum:
Better and worse dog life jackets - Cruisers & Sailing Forums