I love mine. I can't use tampons (because of the shape/size/arrangement of my cervix) but I can use the Diva cup, which is great.
I usually have 1 day per cycle where my flow is really heavy, and I have to empty it every 4-6 hours. The rest of the time (the other 6-8 days of my period, blah), I can go 12+ hours without emptying. I don't NEED to use pantyliners, even when I'm exercising or sleeping or anything else, because it's 100% leakproof for me... but I still do of course. :P
I've never boiled mine... I wash it really well with anti-bacterial soap and rinse it with hot water EVERY time I empty it (other than in public restrooms). I got a great tip recently to wipe it with rubbing alcohol once a month, to keep it from getting so discolored. It works great.
If I had to use pads with my tight stretchy running shorts, I'd never go running, lol. And this way I can still sleep naked like I usually do.
And it's a money saver!