Has anyone just eaten ready meals from MandS on this diet. Do not trust myself to count calories on every item I cook.

M&S ready meals are generally good quality, and they do have the calorific content on the back (small print though) and some details can be found on the internet.

However, watch for
a) portion sizes – you generally don’t need very much of them to keep your calories down
b) carb content and added sugar

But if you have something very simple, such as meat and look very carefully at the contents of sauces for sugar etc., they can be good. I have had some very nice fish from there but generally not the ready meal sort, just plain and cooked it myself.