I would recommend against getting anything domestic or even European imports in the UK. Blueblood, LVC, Corpus, Evisu, Nudie, are much more expensive London than in LA or NYC. London prices make NYC prices look like everything is on discount. Corpus and 5EP are available for under $200 in the US, the former available for under $150 if you know where to look. Blueblood can be had for $125 on sale in LA. In the UK, 100 pounds doesn't get you nearly as far for US brands. And don't even think of buying the more mainstream US brands in the UK, unless you like paying double, in which case, buy in the US, then PM me, and I'll tell you where you can send you excess cash. With that in mind, there are some really decent UK, European and Japanese brands that are difficult to find in the US. Atelier being one of them. Of the more mainstream brands, I would recommend One True Saxon if you are into the skater look, Seal Kay for something a little more mainstream, and Firetrap and if you are into the cheap and easy. Duffer has pretty decent denim nearly inaccessible in the US, and does YMC. Speaking of which, you should definitely check out the Londons streetwear places. I would highly recommend YMC (You Must Create), 6876 (which is pretty much inaccessible outside the UK and Japan, and is great for basics with a twist (hate that term - I lknow everyone else does too, sorry), Maharishi if you like skater influenced stuff, and Duffer, as ringring has suggested already. Also, in addition to ringring's suggestions for multibrand stores (Duffer is, but the main draw there is their house line), I would recommend that you visit Browns (designer) and Browns Focus (directional) on Molton Street, which carry some of the coolest gear in London.