Seems on the discussion of ground rods, both work fine as long as the rest of the system is not mixed. I included some info from various sites.
From this site.
http://www.ibiblio.org/farming-connection/grazing/features/fencemis.htm
High-tensile, smooth wire, electric fencing is the fastest and most affordable fence that I know about, and its technology has drastically improved over the past 10 years. But many folks are hesitant to use it because they remember old failures -- wires breaking, chargers starting fires, wet vegetation shorting out the fence and other troubles.
With a little commitment and a modest investment in time to learn how to use this new technology, you can save thousands of dollars and hours of maintenance time by making electric fencing work for you. So you won't have to learn the hard way, here are 17 common mistakes that you should avoid:
Poor earth grounding. Lots of folks (including me) still think you can skimp when it comes to adequate earth grounding. What we must all learn to do, is install several ground rods -- at least three that are 6 to 8 feet long, galvanized, and attached with good ground clamps. The electricity must complete a full circle back to the charger through the ground. Poor grounding gives weak shocks.
Using different types of metals. Don't do it. When you hook up steel wire to copper something call electrolysis happens and the metal becomes corroded, making a poor contact and weakening shocking power.
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From http://www.parmakusa.com/Baygard/tips/grounding.htm
A good ground system consists of three six-foot long galvanized ground rods, 1/2 inch thick, spaced 10 feet apart. The ground rods must be connected with insulated cable or galvanized wire attached by means of a ground rod clamp. Simply wrapping a wire around the ground rod makes a poor connection.
Copper ground rods are OK, but connecting galvanized wire to a copper rod will result in corrosion. Eight-foot ground rods are often available, but they are hard to install and don't need to be so long. If you can't find six-foot ground rods, galvanized pipe will work. If you use pipe, be sure to plug the top end to prevent water from collecting inside. Where rocks prevent driving ground rods, bury a long (20+ feet) galvanized pipe in a trench as deep as possible for a ground system.
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http://www.electrobraid.com/manuals/page4.html
2) Install a Good Ground System.
Poor or improper grounding causes 95% of all electric fencing problems. You can have the most powerful energizer in the world, but if you don’t have sufficient grounding your fence will not perform. For "best" results use a minimum of three six-foot long copper clad ground rods spaced at least 10 feet apart. Use brass ground rod clamps to attach heavily insulated copper lead-out wire from the energizer to the ground rods. The drier the soil, the more ground rods you may need. We strongly recommend you use a Positive ("hot")/Negative ("cold") system by grounding ("cold") the second-from-the-top strand and electrifying ("hot") the remaining three strands of Braid™. This will ensure the animal receives a shock when it touches both a negative strand and a positive strand at the same time regardless of the soil conditions.
3) The Correct Materials.
Using garden hose insulators, household electrical wire, improper insulators and other materials is not recommended as they will cause increased maintenance and will risk injury to your animals. The use of copper clad ground rods, copper split bolt connectors and copper lead-out wire are required to prevent electrolysis at the electrical connection points. Substituting non-copper materials will: create problems with electrifying the fence; increase maintenance; and reduce the life span of your fence.
