So I am about to start assembling my first plane with a Pull/ Pull cable system on the Rudder. Are these dependable? Should I swich it to Pull/Pull pushrods instead?

Pull-pull cables are fine if properly installed. Follow the directions and you should have a reliable and durable linkage.

One thing to be aware of: you need to build in something called "positive Ackerman" to ensure the cable goes slack on the non-pulling side as the rudder moves away from center. It doesn't matter whether you use cables or rods...

See here: http://members.cox.net/bdfelice/Pull-pull/pull-pull.htm

If you are sloppy and build in some negative Ackerman then the geometry will be such that the non pulling side of the cable pair will tighten as the rudder rotates away from center. Since it is hard to build it perfectly neutral, a good way avoid to problems it is to intentionally add a bit of positive.

About all I ever use on my big planes (also on some of the very small ones) is pull-pull cables and have never had a failure in some 15 years of using pull-pull. The comments above of being sure that there is just a bit of positive Ackerman is a good and valid one. Also, leave the cables as loose as possible, just enough tension to have no slack at neutral position.

About all I ever use on my big planes (also on some of the very small ones) is pull-pull cables on both elevator and rudder and have never had a failure in some 15 years of using pull-pull. The comments above of being sure that there is just a bit of positive Ackerman is a good and valid one. Also, leave the cables as loose as possible, just enough tension to have no slack at neutral position.