I noticed that Sainsbury's have something called 'Chocolate Os' which look something like I think Oreos look like.

Won't do.

Oreos have a very specific smell, texture, and flavor that I haven't seen duplicated anywhere else.

Even here in the US, there are a lot of "generic" cookies that imitate the style of Oreo, but somehow don't quite match them exactly. For instance, the Sunshine company made a cookie called "Hydrox" which looks like an Oreo, and tastes something like an Oreo, but isn't.

The other thing you need to know is that Oreos must, without fail, be absolutely fresh to be any good. The package must be fresh from the store, and freshly opened. Oreos that have spent time in a cookie jar with other stale cookies should be considered poisonously contaminated and should be discarded. (I've heard that some people prefer the taste and texture of stale Oreos, but I can only conclude that they are slack-jawed, mouth-breathing, knuckle-dragging troglodytes who can't possibly understand the finer points in life.)

Additionally, Oreos must be eaten with a big glass of ice cold milk to be enjoyed properly. There can be no substitute.

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Tony Fabris