It's not sex linked, so yes, same results. Mind with the leakage I bet you get the same results as a black x buff cross which almost always results in a very weird bird with more leakage than normal, and tends to end mostly buff on the top 1/3-1/2 and black (blue in this case) on the bottom 1/2-2/3.
It's similar to how you describe roses, yes. S/s+ comes out as mostly silver with some golden leakage. A good example to look at are Silver and Golden Duckwings and Black Breasted Reds. Silver Duckwings are S/S. Golden Duckwings are S/s+. BBR are basically Red Duckwings (with red enhancers like...
It's 100% dependent on what the white hen is hiding and what kind of white she has (breed and individual dependent factors). If she's dominant white, 100% of the offspring will be white, probably with small amounts of color leakage. If she's recessive white, the offspring will be the result of...