[oldE]

We have used ElectroBraid for about 20 years. I like it because you do it once and you're done.

As above, I used an auger and 4x4 8' pressure treated posts, spaced them 50'.
The Electrobraid folks recommend four strands of wire rope: top, second down and the bottom are "live" and the one above the bottom is ground. We used only three as our horses are not "jumpers" and even the miniature donkeys respect it.
It will streatch in heavy snow but will tighten back up on its own. If not a few minutes with a come along and a couple of wrenches and you're done. (Don't forget to unplug the energizer! You won't forget a second time.)
Grounds are of paramount importance, about every 500 feet.
There is lots of help on the website regarding setting up their product and they even throw in a tester.

I'm not affilliated with the ElectroBraid folks, but I certainly recommend their product.
Mostly because I grew up on a farm and fenced every spring for over thirty years before switching to the braid.

Best
Les