> However, when I am searching for a pressure cooker, it would be great to go to a centralized repository of ads and look through who markets this sort of thing the best and may be have some objective reviews along with it.

The Wirecutter used to be pretty good for this, until the NYT bought it. It's still OK now, but it feels like that the pool of products being reviewed in each category is smaller than it once was. The whole site is basically a giant ad/referral scheme, but as long as you're aware of that then it's not bad as a starting point for research.

I used to just do a search on Amazon and start from there. Now it's 1 or 2 big brands followed by 20 pages of the same identical Chinese clone product with names like "Wootoo" and "Yungoo".