I don't have any hard data on pros or cons for silicone. I think it's telling that OEMs don't use it though. I don't think it has the same abrasion resistance, and can be too slippery. My understanding is the main reason that silicone is used for large turbo hoses is because it's relatively easy to form into custom shapes, not because it is inherently better. That doesn't apply to small diameter straight hose of course. Though I do wonder if silicone has enough structural integrity to not collapse under vacuum.

FWIW I have had silicone turbo hoses fail. (Link to large pic: http://www.boost-instruments.com/gle...7/DSCN1164.jpg ) All hoses can fail of course, my only point is that silicone is not necessarily superior in every way.