I've had some great advice about bras on the chat board - I didn't know there was a style and beauty board!
I've decided that Bravissimo own brand bras suit my shape more than Fantasie/Freya or Panache/Cleo and I've finally got some potential keepers - Tartan Fling, Candy Bliss and Floral Haze. I was measured as a 34GG instore but had the 4 boob effect so went back to my old size of 34H and I feel they fit ok. Sadly I keep escaping from the Purity moulded bra so I think I'm just the wrong shape for a moulded cup!
However (this couldn't be straightforward!) I decided to measure myself using the method on the bra intervention threads. I'm a 35 back and when I do the 90 degree bit there's 13 inches difference. Does that make me a 34/36J or have I done something wrong?