Last summer fenced 8 acres + paddock, PT posts & 2X6's for paddock with hot scare wire over all boards (I have a cribber and chewer!) Pasture is 2 strands wire + 1 top strand rope for visibility, all wires electrified. Used springs for tensioning wire and rope. Tree fell in 1st 30" storm in March, dropped fence, nothing broke. Got the tree off after the next 30" storm melted some and it popped back upright.
Used 6" round PT posts, on corners and fiberglass rod posts in between. The rope withstands snow and wind better than tape plus lifespan is longer (depending on what you buy. Hi tensile was not recommended for horses (cheese cutter effect)
Check out Premier fencing - they sell sheep, cattle, horse, deer, etc. Good instructions & recommendations in catalog. Web site
http://www.premier1supplies.com/ Good info for decision making. The chargers are not cheap. Have had cheap charger and you have to do a lot more line clearing to keep the shock. Good grounding is essential no matter what charger. Premier explains this, and how soil conditions affect (snow, wet, dry) grounding.
I also checked out Ramm fence, but Premier has better how to do information.
You could spend a lot of money on fence.