Hi isobel,
I am a regular tesco shopper as I live next door to one (literally!) and have watched the introduction of the new healthy ranges they have introduced. Here's my thoughts:
There are 2 ranges: "Light Choices" (generally in white packaging) and then "Eat Healthy" ( i think?!) which is in green packaging.
Having spent hours in store comparing the various products, my conclusion is that the "Light Choices" in general aren't that light! Ok, so they do not contain quite as much fat or calories as the original versions of the products but they are definitely not particularly good! Comparing the lightest "light" ready meal I could find (chicken and gravy pie- basically chicken, carrots and gravy with a teeny bit of mash on), with a standard weight watchers ready meal, there were over 150 more calories in the "light" meal and much more saturated fat.
Looking at the "Eat Healthy" choices I was much more excited! The meals are made like you would make a proper meal at home, not just a blended mush of ingredients. I had the salmon the other day and like most of the other Eat Healthy ready meals (they also do Eat Healthy fish, chicken, turkey and products that aren't ready meals) it had a generous portion of the fish in a yummy sauce with nicely done and presented veg on the side (not smothered in sauce) and a couple of potatoes. It looked like a meal you would serve up freshly cooked on a plate with the only difference being it is sold in a tray with film over it to keep it preserved and make it suitable for microwave cooking.
In terms of nutritional contents, the Eat Healthy choice is much better than Light Choices as they seem in general to have a low cal content (especially considering a lot of them have really tasty sauces- Beef Bourgignon yummmmy and also they have plenty of carb-type foods like noodles, pasta and potato but yet the cals stay low) which I was really impressed with. The fat levels are also lower.
The only thing is, you get what you pay for. The Eat Healthy food is more expensive, quite significantly so, but I personally think they are worth it. The Light Choices are cheap. I have tried and a couple of them are ok but are very calorie-laden considering how little food you actually get in the particularly small trays they come in (in the Eat Healthyn trays they are bigger and you get more food for less calories/fat!)
Comparing with Weight Watchers I would say that the WW is probably better in terms of fat/cal content, but the portions are small (about the same as Light Choices) compared with Eat Healthy range. I also think having sampled most of the WW meals that the Eat Healthy stuff is tastier. I would say if you are concerned about money then out of the three I would choose WW, but if quality and healthiness is more important then the Eat Healthy is better,
(i am pretty sure its Eat Healthy- it could be Be Healthy but i dont have anything in the house to check at the mo!!)
Sorry I cant help with other brands very much- I have used M&S a few times which was delicious but not overly healthy compared with the normal supermarkets light options or WW.
Hope this is useful xx