I'm of the opinion that you can't really go wrong with a blog. You can target many keywords that are out of the range of possibilities for a product page (i.e: product A vs. Product B comparison). Also, it is easier to rank a blog article because of relevance etc. You can just get the readers and provide something useful enough that they explore the site or even have links on the side if they're interested.
Also, if you provide content that is good enough you can backlink the crap out of a blog article and usually not get penalized too bad. Yet, it will provide root domain with trust/authority.
But that's just my analysis.