Well, the Mooncup arrived today, which happens to be the second day of my period, so I went to the bathroom to take out the Diva and try the Mooncup. I inserted it, stood up, walked to the next room, grabbed the scissors and went straight back to chop off the entire stem! It took about a millisecond to decide it had to go... and NOW I understand what people have been talking about when they complain about the stem poking them. :)
Anyway, so far so good. I have the smaller sized Diva but decided to go for the larger Mooncup. It feels just as comfortable so hopefully it will just as happy up there as the Diva has been. And I like that Mooncup provided a couple of advertising stickers - they'll be going straight on the back of the toilet door at university!