Sinking Lines and Sink Tips in Rivers

[smallmouth]

I've had a lot of success fishing a fast sinking full sink S.A. line in stillwaters and would like to explore rivers and streams with a sunken presentation. I have been looking at the "Streamer Express" and the "Wet Tip Express" both Scientific Angler Lines.
Is anyone using either of these S.A Lines? I want to purchase a new line for stream fishing and don't quite understand the concept of the Streamer Express. It has an intermediate running line which sounds good for stillwaters or pounding the banks from a moving boat but obviously would not mend very well for nymphing or dead drifting. I love to fish streamers but perhaps my original interest in this line is misplaced and I would be better served by using the Wet Tip Express. Anyone with experience who can offer positive or negative feedback on these lines?

Is it possible to fish streamers with my full sink line in moving water?