I was diagnosed with PCOS the beginning of this year. Which really I am surprised I didnt recognise the signs earlier as I have had a lot of the classic symptoms since I was young. However it only really seemed to cause me issues in the last couple of years and I expect the weight gain and other problems when I was pregnant with my son didnt help.
Slimming world is a great diet for PCOS sufferers, you just need to try to avoid "white" carbs which have no health benefits what so ever. Stick to whole wheat where possible and try to limit potatoes. New potatoes in skins are better. I also recommend googling low GI foods and incorporating those into your free food choices.
I have noticed my weight loss comes off a hell of a lot slower since my diagnosis, but I just stick to it as a way of life now and as long as the weight is coming off and not on then that is all that matters to me.
I do notice I get terribe bloating when I do occasionally have the higher GI foods, so I avoid them most of them time.
I am also on metformin - 1500mg a day