Okay, so not quite an apples/apples comparison since the lighting is different and what not but here is a shot with the 16-35L @ 30mm and one with the 85mm prime. All I did was resize down to a max dimension of 800 pixels horizontally (no unsharp max after resizing, either). I included links to the originals if you're curious what the full sized looks like.
85mm prime:
original w/ 85mm prime
16-35L (@ 30mm):
original w/ 16-35L @ 30mm