For protection in case I have leaks, I recently started using period panties. I usually wear them for 5-6 hours at a stretch.
There are definitely differences between the brands. I shopped on Amazon and I like the Modibody as well as the Bambody underwear. These have the absorbency at the bottom of the panty only, without coverage going up the rear. If using them to sleep in during the time of menses, I can see the need for rear coverage. However, for riding, the lack of breathability due to a wider area of coverage was an issue. They became way too hot and sweaty. Look for panties with a leak proof lining only where a pantiliner would cover. Both of these brands are quite comfortable to wear and I don’t really feel a difference between these products and regular underwear.
Any of these panties need to be line dried only but can be machine washed. For some weird reason the Bambody panties take a long time to dry, so if you are only purchasing a few pair, keep that in mind.
I am hoping that in the hot summer, these will be more comfortable than using a pantiliner, which end up shifting if you get too sweaty.
I haven’t had any major accidents to test how leakproof they are, but they have held up to tiny leaks so far. I guess my major test will be the next time I school cross country-especially drop fences!