I had great success with Cambridge, and I have pcos.. but I wasn't on metformin, so it might be worth checking this out with your gp.. It's serious stuff going onto the cambridge - worth it if you take it seriously, but it's important that you do take it seriously. I came off it too quickly and ate the wrong things and gave myself gallstones which needed my gall bladder to be removed. I also feinted one day cause I was on 3 packs a day only for a while and loved it, but accidentally went out dancing and drinking water for the evening and collapsed with exhaustion.. so be careful.. but if you do it right it's FAB!! Pcos shouldn't matter.. but do check about the metformin because it is prescribed for diabetes to control insulin/glucose levels so might be worth checking
Good luck - and enjoy it - once I got into CD I absolutely loved it, and have no regrets/ no doubts about the benefits
xx
Vxx