I've been taking Loestrin 24 for seven months now, and it worked like a charm - my periods haven't exactly decreased in time, just in heaviness (my periods weren't really heavy to begin with). No side effects, no spotting, nothing.
But this might be something to watch out for:
This past Saturday I was too lazy to take my pill in the morning, and I stayed over at a friend's and didn't take my pill Sunday either. Saturday I ate a bunch of junk food (pizza, brownies, etc.) and I bloated... which made sense. So I just tried to drink water. The next day I began cramping... which was unusual. I would be just finishing the second row of pills and I can't say I've knowingly ovulated since I've been taking these pills. I come home and to my horror, I was spotting... which has NEVER happened before. And as the day went on the cramping hurt more (not overbearingly but there was a noticeable change) and I noticed the blood smelled HORRIBLE, like a mix between a rotting animal and vomit. And today I'm still spotting.
To make a long story short, I now have an appointment with my gyno. I don't know if it means anything, but don't be like me and purposely not take your pill... you're supposed to take a pill a day for a reason. ):