Tesco Wheat Biscuits are exactly the same as Weetabix, if you check the label the ingredients, quantities, energy info are identical, wouldn't be suprised if they are made by the same company. They are a fraction of the price. Sainsbury's Wheat Biscuits are also equally good.
The following comments apply to both Sainsbury Basic and Tesco Value ranges: (I have 'taste tested' both ranges)
Cream cheese, exactly the same, tastes every bit as good. I think Tesco Basic Cream Cheese is 45p/tub whereas as Philidelphia is well over a pound.
Value porridge oats, as good as more expensive ones and much cheaper. Likewise tinned tomatoes, kidney beans, tortilla chips.
The big 3kg bags of pasta work out much cheaper than any other way too.
Value/basic frozen peas/spinach etc, just as good and a fraction of the price.
Tesco basics sultanas and apricots - a fraction of the price to the other ranges.
The market value/basic etc ranges of fruit/veg - the quality is just as good, the sizes are simply smaller/less even.
The Co-op simply value eggs (with the yellow writing on the box) are Free Range Eggs and are a fraction of the price of the others, the only difference is that they come in different sizes so you have to work out your own egg size. My MIL keeps chickens and let me tell you, they don't come out of the chicken with the size printed on them! Common sense and a big saving to be had.
I wholeheartedly agree with what someone further up the thread said, when it comes to 'single ingredients' eg. porridge oats, as opposed to something 'already made' eg. pasta sauce, it is often as near as good a quality/taste as the more expensive range.