Even big and famous brands sometimes send generic replies that are not very helpful. I have learned to avoid items that look extremely different in every product photo. Smaller shops can be surprisingly friendly if they care about repeat customers. If anyone has long term experience with certain online shops, I am always curious to read it.
If anyone is interested in real user experiences, I sometimes write short notes about the shops I test.
You can find one of the pages here:
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It is always difficult to know which website is really trustworthy before you place an order. If a deal looks too good to be true, it usually has some kind of catch. If buyers say the item runs small or large, I always adjust my choice accordingly. Sometimes I experiment with different materials just to see how they feel in daily life. Sometimes a store looks great in ads but the real product is completely different. For coats and blazers I usually go one size up if I want to layer sweaters under them.
Maybe this is useful for someone.