D&G, the quality of it is horrendous, especially for the price you pay. However, it's a nice item to buy when you're looking for some decent street wear and dep't stores such as I.T. in Hong Kong offer an up to 90% off invite only sale which stretches to the likes of D&G, Raf Simons and Viktor & Rolf

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That, and these days Dior Homme. In the past I have been willing to dish out well over a couple grand on just one or two items (circa reflection - strip), but that's due to the fact that, during those days, I could say that the quality really did speak for the price. Unfortunately that isn't the case anymore (though occasionally it is for the rare runway piece). Case in point, I bought a $475 shirt from their previous summer collection and within just a couple months the material just started to lose it (I only wore it perhaps a total of six times as well), and I was gravely dissappointed. So for me, Dior Homme, nowadays is way up there on the list, which really is too bad.
Not to mention, trashy labels like DSquared2 and Lucien Pellat-Finet (their cotton items that is, as their cashmere pieces are truly unmatchable), oh yeah, side labels like Versus and Versace Classic!

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Sometimes I feel I must defend Prada, as I have had some very good puchases with a couple of their items (Suiting, Cashmere Turtlenecks as such), however I will admit that their tacky Prada Sport items are ridiculously priced.
Anyway, the ultimate markup I must say is the whole Nike Dunk and Bathing Ape (street wear) craze. In places like Hong Kong and Japan, you can easily find a pair of Nike Dunk SB's for $3-500 USD (these are regular Nike Dunks, made in China, only with "limited edition" color schemes) and even $5000 USD for something like the Undefeated crossover with Nike (one of these is simply an all white Nike Dunk with the undefeated logo sewn into the back). This I must say is ridiculous, because it's simply all hype, no quality. The unfortunate thing is that these crazy items continuously get sold and in fact, get sold out in no time!
- Cheers