I disagree.
Like puck2 I too eat the Mainland Vintage Cheddar.
At just over 200 baht for 250g it is not only very tasty, but also good value.
Just as good, if not better then the Waitrose Extra Mature British Cheddar from Tops. Which is almost double the price of the Mainland one.
Having left the UK over 30 years ago, my memories of decent cheddar in the UK are very distant but I definitely rate the Mainland Vintage.
It is the one in the yellow/gold wrapping. Their other offerings are pretty sad though.
As a footnote, my favourite was the Mexican spicy cheddar that TOPS used to sell. Sadly no longer available