I’m in India on the 3rd day of my period and so far I’m a HUGE fan of the Flex Reusable Disc. If I had known all the benefits I would have changed to a disc years ago. I noticed yesterday that there’s a little notch where you can fold it which could explain why it was so difficult to get in the right place at first. Basically it’s a firmer rim and a very soft and thin silicone “cup” in the middle.
First of all, the capacity is twice that of the Lunette. And it auto-dumps if I bear down while on the toilet! So no need to manually empty it during the day and I just need to remove it in the morning and evening when I’m at home to rinse it off (otherwise I’ve learned that old blood gets very gross and stinky). It’s much lower profile to insert than the cup and comfortable once inserted properly and does not press on my bladder or block my urethra. And it hasn’t leaked a single drop. With the cup it always leaked and I’d have to wear a backup pad. And I hear that you can have sex with it in, which I haven’t tried yet 
I bought my Flex Reusable Disc new (damaged box) from eBay for cheap and now I don’t know what to do with my two Lunettes. The big one was only used for a few months and I found it much firmer than my old one, and the smaller one was only used once. They’ve been boiled for a good while. If anyone in the U.S. isn’t squicked out and would like them, send me a message and I’ll mail them to you after I get home!