Try Adidas AdiStar bibs. I have them as well as PI Ultrasensor shorts and the AdiStar's are my favorite. The bibs I bought in April had a read chamois and I jsut bought two pairs of 3/4 length nickers and they have a blue chamois. I was worried at first that they changed something that worked so well but the new blue ones are even nicer than the red one. A bit thinner and just as comfy on long rides. They also wear very well. I have about 700 miles on my AdiStar bibs from April and they still look new. I also have LG Ergosensor bibs and they're great.

Another data point on sizing... I have medium PI Ultrasensor shorts and my Adidas bibs and nickers are medium as well, as are my LG bibs.