I'm 42 and a size 12 hourglass.
M&S - for skinny jeans and occasional Autograph slouchy t-shirts, plus knickers and tights.
Hobbs - full price or sales for basic plain tops and their Outlet bit for jackets, bags, etc. Their dresses, trousers and skirts are genrally too long for me and I don't like many of them anyway.
Oasis - for jeans only. I also got a fab biker jacket there. But most of their stuff is made from really horrible fabrics and v expensive for what it is.
Vivienne Westwood sales - great for hourglasses!
The White Company - for v plain jersey dresses
V occasional bits in Topshop, especially a brilliant plain black column maxi skirt. I had to search through lots and lots of rubbish to find it though.
Warehouse for silk camis, tops and occasionally dresses - they are not as good at these as they used to be though, sadly.
H&M for cotton blazers and cheapo scarves.
V occasional bits in French Connection, but again I find it v overpriced for the quality.
Tbh I'd rather shop in more 'old lady' shops like Hobbs and The White Company and get the quality, then mix with cheap scarves etc to dress things down.
I find Mantaray v 'mumsy' and over-colourful, and Phase 8 just doesn't do much for me and is stupidly expensive for what it is, and not v good quality. I refuse to go into New Look and Dorothy Perkins anymore as I just think they are awful. Zara seems to have a few nice things online but their sizing is ridiculous and I loathe the shops, so have given up on those too. Don't like Great Plains stuff, as again I think the fabrics are mostly pretty horrible. In fact, I'm frequently surprised that I have anything to wear at all!