The vegan Cathedral city is my favourite alternative, melts the best too
I’m dairy free as have a cows milk allergy and find for cheddar equivalent either Cathedral city plant based or Chedderton mature. La Fauxmagerie do some really special cheeses and at the moment ALDIs spread is good, but otherwise Philadelphia plant is good for cream cheese
The M&S slices are very good, they melt well too! Otherwise Cathedral City, the extra mature (black) one is actually a better cheddar taste x