You may not remember me, but I posted last July or August asking for advice on switching cups. I had been using the Diva cup for the past three cycles with partial success: I was able to get it in, open, and correctly positioned just fine and it would work well after my first insertion, but it would leak within five minutes of re-inserting it. No matter how I put it in or which fold I used, it would constantly leak. I had to wear pads for back-up because I never knew whether the Divacup would leak or not.
After three cycles of struggling with the temperamental Diva, I came here to ask for advice on switching to a MoonCup UK. I had recently converted my best friend to the wonderous world of menstrual cups, and she ordered a MoonCup UK for herself, on the principle that she would never put anything called a "Diva" anywhere near her body (she's not a very "girly" girl :-P). After she reported no-leakage success with the MoonCup, I was tempted to switch from the Diva.
Thanks to the wonderful advice and support I found here, I was convinced to make the switch, and have been using the MoonCup UK with great leak-free success for the past six cycles. No matter which way I insert the MoonCup, it insists on working, and works very well for up to 8 hours on my heaviest days. So, thank you all for your help and for leading me to exceeding happiness with my MoonCup! And to anyone else who is considering switching cups, I would highly reccommend it. It's worth the extra money to find a cup that works well for you.