I second what Fergie says and in fact it is illegal to use electric mesh fencing with horned sheep. Also, sometimes a polled sheep will stick it's head through an electric fence and get stuck by the wool, with the same result.
With stob and mesh stock fencing, you don't have to run barbed wire along the top. We have banned the horrible stuff here and just use a strand of plain wire. All the barbed wire does is damage animals and humans alike; it doesn't stop animals jumping, just tears them when they do - good news for the vet
Stock fencing is expensive but quite honestly it's worth having good quality fencing - a sound investment.