I challenge you to provide me a better resource than reddit for finding reliable product reviews and discussions for just about anything you can buy.
If you need to actively find a review for some item you want to buy it's probably not that great of an item imho.
Furthermore, 4chan has no search feature so I don't know how that's even equivalent.
/g/ has "an audiophile general" for example that comes with recommended places to buy, tierlists and reviews.
The problem with reddit is that just because someone recommends a product, doesn't mean they actually bought/experienced it. That being said it is a great way to find a product's defects, as people usually post to reddit.