What Shannon said. For some items that are indisputably good and fit my style persona, I have no question whatsoever. And I usually won't post a K/R thread on those, unless it is a question similar to some of your "is this worth it" questions --- you know....wondering if the expense sort of balances the aesthetic value in some way. As in , I love this, but am I crazy to spend this much money on it given my budget, or is it reasonable under the circumstances. That kind of thing.
There are other items that I feel less sure about, and I definitely love getting input on those. It might be fit, or colour or who knows what. Also, as Diana said, I like to take the photos and see the photos, because they tell me something different than the mirror.
And then the forum opinions also help.