I've spent most of today reading this thread and felt the need to add my .02 cents. I first tried Instead and still keep them around. When I first purchased them I wasn't very familiar with my anatomy so I got to know it very well pretty quickly. The only issue I've had with the Insteads is that the push against my urethra and make me feel like I have to pee ALL the time. I do still use them for less messier sex on my heavy days.
While still using the Insteads I was researching to see if I was just using them wrong and if that was the trouble I was having with them. That's when I came across the reusable cups. I saw that a local natural food store sold the Diva so I went and got one later that week. I got the smaller size (since I was 21 and nulliparious) so I was following the guidelines. The stem drove me crazy!! The Diva brand is the longest of all the reusable cups. So I went home and hacked off the stem and rounded off the bottom. Too bad that didn't work either. It seemed to lodge itself right behind my pubic bone no matter how far up or down I put it in. One again to the internet I went in search of a cup that might work better. I really wanted a LadyCup but at the time it was one of the more expensive ones so I got a Mooncup Uk instead.
Now while the MCUK still didn't work quite right for me it was still night and day with how the Diva was. Everyone on the Menstrual_Cups website on LJ said that the MCUK popped open great (which I had some issues with with my Diva, although never a leak) but for some reason I could never get it to pop no matter how much I manipulated it. My first day at work with it I spent almost 20 minutes in the bathroom trying to get the thing to work and finally had to suck it up and go back to mu Insteads which I always keep around just in case. Also trying to get it out after it wouldn't pop open was complete torture, probably because I always wound up spending so much time poking around up there it was just completely painful. I'll admit I cried a couple times.
Finally I broke down and bought my LadyCup size small & large. They are amazing I guess I should have folled my gut about it to begin with. it's so much softer and squishier than the other cups. There aren't any ridges on it like the other cups, it just has raised bump and a slightly tacky texture so getting it out was more complicated at first but I figured out my own little dance routine that works well for me.
Mostly what I'm trying to get through with this post is that there are so many more brands, shapes, and sizes than just the Keeper, Keeper MoonCup and Diva.
Here are some links:
Lunette ->
Lunette
LadyCup ->
LadyCup menstrual cup
Miacup ->
Miacup: Rethink the tampon
Femmecup ->
Femmecup - The future of feminine hygiene
Mooncup UK ->
Mooncup Menstrual Cup
Diva ->
Home - DivaCup™
Keeper / Keeper Moon Cup ->
THE KEEPER® THE MOON CUP® Manufacturer, Home Office, Distribution Headquarters
Also If you are interested in buying one check out ebay I know that LadyCup and Mooncup Uk are both from very reliable sellers and slightly less expensive that way (it's how I purchased them both). If you want a certain cup don't settle for what is more available (ie the Diva for me) go with your gut. You know your body best.
Ok I think I'm done ranting