Renee G.wrote a review of SmartWool Microweight 150 Hiphugger Underwear - Women's on January 8, 2013
Familiarity: I've used it several times
I bought 6 pairs for a trip. 5 have held up great, 1 fell apart after about 3 washes. While this is clearly an anomaly it prevents the 5 stars.
That said, they don't ride up. They fit really well, feel weightless on, clean easily and dry quickly.