I have had these for a short while, but they are the same as Castelli's Wicked shorts from last year. The fit is the same as the Wicked. I also have the white color. You can see through the white but the black is strategically placed so that you are not getting that much of an eyeful. You do not need to get these wet for their transparency to reveal itself :)
You have to be looking to see through and you would have to be fairly close. Unless you have to have white, I might opt for the grey. The red from last year is see through also, but not as much as the white.
The straps are very comfortable and the chamois is also nice.