Word of warning - Adidas' UK sizes are half a size out,
Adidas trainers are a very tight fit (or at least the Sambas I had were, though I'm led to believe this applies to all of them). As far as I can see the reason is simple- Adidas's UK sizes are half a size out, compared to almost all other trainer makers'.
Most manufacturers' labels say their US size 11 shoes = UK size 10, and US size 10.5 = UK size 9.5. For some reason Adidas's say that US size 11 = UK size 10.5, and US size 10.5 = UK size 10.
So I buy a pair of UK size "10" Sambas, and they're tight. Actually tight enough to affect my walking style (should have spotted this in the shop, but I was in a hurry and they seemed okay strolling up and down a couple of times). In fact, I'd say they were about *half-a-size* too small... hmm, that's probably not a coincidence.
I should make clear that I'm *always* a size 10 trainer, and the only other pair I can remember being a bit tight for their own good were... some Adidas Super Sambas I had a few years back.
Anyway, I don't care what Adidas says- their UK size "10" Sambas are actually a UK 9.5 and I should've gone half a size bigger to get a "real" size 10.
You may want to consider doing the same.