It pains me to say this because I am a loyal Castelli customer, but after 2 seasons of trying to love these knickers, it's time I admit that I hate 'em. The Progetto X2 chamois is the best on the market imo but it's way too far forward and doesn't cover my sit bones in the saddle. I'm constantly adjusting it on the bike, trying to pull down in front and pull up in back. As a result of all that pulling, I've popped a bunch of stitches in the thighs - poor quality workmanship. Also, the leg grippers don't hold (and I have large calves), especially on long seated climbs, and they eventually ride up to knee level. Again, I'm constantly adjusting them on the bike, pulling them back down. The hallmark of a great pair of bibs is you don't even think about them while riding. Well, that's certainly not the case with these.