I really like my PI AmFib tights. In addition to the wind/water resistant front, it also has a nice booty panel in the back for the "honestly, I swear I didn't just crap my pants" mud stripe.

More importantly for me and my shortwaisted torso - the AmFib tights are nicely scooped down in the front. Similar to the way the Sugar shorts/knickers are dipped down. The back is nice and high. When you're in position on the bike it's perfect. (I usually end up having to roll the waistband down a few turns on other tights because the waistband cuts into my digestion.)

I mainly like these tights for cold and dry weather, or for light precipitation shorter rides. For real rain, just get waterproof rainpants to put over shorts/tights.