OP YANBU, menstrual cups are brilliant! I use a meluna and have done for the last four years. It turned periods from being a painful, messy hassle into just another day.
I can tell with mine when it is going to need emptying as I get a 'full' slightly heavy feeling. I empty it at 7am when I get up and then don't need to empty again until I get home from work at 6pm so rarely need to empty it at work. Then I empty it again just before I go to bed. Have never leaked with it, I'd say I have a medium-heavy flow.
It takes a little getting used to, so the first few times I'd suggest trying it on a day/evening when you're at home. Bear in mind that if you don't wear it from the immediate start of your period you will prob need a liner as back up for the first hours as there will already be blood in your vagina that hasn't been caught by the cup. I track my cycles and usually know when to expect my period, but because there's no risk of TSS you can put the cup in 'just in case' if you think you might get your period that day. That's a massive bonus in itself - no getting caught out.
I fold mine in half lengthways, insert it and then rotate slightly so it pops out into place. I think it depends on your cervix etc as on the leaflet I got with my meluna it shows the cup just held in place in the vagina, but I find it suits me best to sit it over my cervix like a little hat. I then run a finger round the rim to check its popped out and in place. And then forget about it for the next 12 hours!
To get it out I just squeeze the main body of the cup to break the seal, twist very slightly and then just gently wriggle it out. i don't use the stem so cut that off, but meluna give you the option of ring, stem, ball and no stem, plus come in lots of different sizes and colours. this is their size guide to help your work out your size. And here is the website I got mine from, they have a huge range of all sorts of cups.
One tip about emptying it for those who haven't used one before, stick some loo roll down the loo first before you empty it, otherwise can the blood can pool there and take a few flushes to go.
If I'm out and about and I have to empty it I don't bother rinsing mine, just a quick wipe with loo paper if needed and back in. It's really not messy or gross at all, less so than a tampon and definitely less than a pad, and there's no smell with it all.
I have gone swimming with mine in, cycling all day, mountain walking all day. It's hassle free when out at friends or if you have to use a loo where there might not be a bin.
I wish to god I'd known about them from a teenager. I got my first period at 12 and when I think of how awful and messy they were and having to carry/change San pro at school and the leaks and sports and changing rooms. Oh it would have made life SO much easier! I imagine there's a much bigger range of types/sizes available now than when I started my periods 20 years ago, I know you can definitely get them in smaller/softer cups for younger girls/women. My DD is not even two yet, but when the times comes I shall definitely be wholeheartedly recommending to her! The environmental benefits are a tiny side benefit for me, as far as I'm concerned the main massive benefit for me is how easy it makes periods. I almost look forward to them now!
Massive post I know! But the advice/experience of others was invaluable to me when I started using mine and I would never go back to using anything else now.