Typical, mostly useless replies save one from someone who's actually used them...
The chamois in the ibex bib shorts is not as good as the one in the knickers. I've used the knickers and they work great, but wound up returning them as I don't like bottoms without the bib part.
If they improve the chamois in the bib shorts or make a bib version of the knicker I will probably buy one or the other.