I use the chicken breast from Farm Foods - 3 x 1kg bags for a tenner (?3.33 per kilo)! The chicken has added water content and tastes very slightly salty, so they must be processing it in a brine solution. It's perfectly fine for curry. I tried the Morrisons' cheap equivalent to this a while back and it was rank by comparison.
The morrisons near me is pretty rank for chicken, also looks and feels a little harder as if its been stood in open air longer, kind of a plasticy feel.
Aldi I've found is best of the supermarkets for chicken.
Also Morrisons, Tesco, Asda are a bit pricey on too many things. I would urge people check out Aldi or look for some asian shops. Even stuff like chillies or flour has a huge mark up at these three stores. more bemusing is many poor people go to these shops.
packs of bird eye chillies are getting pricey and you get less in a pack that I don't even by these at the main stores on a whim anymore. I can get the equilavnt of 4x 1 quid packets worth for 30-40p at the asian store.
Since I do a lot of curries a week I always get 20KG bags of rice. I save over a tenner plus its much better rice. With the cost of chillies and many other things it runs into hundreds of pounds saved a year.