We run our sheep pretty much all year on land that has no fencing (apart from two lambing fields) so we always use electric fence. Never have any problems.
I use 6 strand or 9 strand poly wire (been warned against netting as tend to get stuck), which you can get from mole country stores but I found agri fence to be the cheapest. Its all on reels to tension it which I put on a metal mounting post.
We use polyposts which are 3ft to hold it all up, then bash wooden tree stakes with insulators in on the corners to keep the tension. Then we electrify it with either MVF 12v 1j or 12v 3.5j energisers attached to 110ah car batteries. Have used agrifence energisers too which are good also. The output of the energiser we use depends on how big an area we're fencing.
Hope this helps.
Oh and you'll need connectors between each line of wire if you've got multiple on different reels.