Best place for Zentai?

Hey lads, Recently bought a couple of suits, pretty cool, but could be better. Can anyway recommend a good place to buy for UK base? I always order a size smaller and it still ain't tight enough for my liking. Also, trying to find one's with the seem center back, so the material can sit right into your arse like on the n2n singlets. Would prefer recommendations rather than people advertising their iwn shop. Cheers all ;p