M&S ultra high impact one is great (not sure of correct name!)
It's got a racer back and hook fastners so no straps slipping down but you still get the extra support. I'm a 36FF and had always had to wear 2 bras (a doreen + one other) until I discovered this one and at £20 excellent vfm!
Yep, i got a shock absorbers bra from robinsons, its the one that zips up at the front and its brillient!! Ive tryed loads from various shops and the zip one is definetley the best. x
i've got a Shock Absorber, Level 4. It has a normal bra strap in the normal place and then another one across your shoulder blades. Really good and a hundred times better than the Level 3 impact one.