I have tape - its rubbish.  Gets all twisted and wires break at the corners.  I have found solid galv wire best, but don't know on the rope, although its got to be better than tape.  Have had no problems with stakes, mine are 4 ft and quite thick.  I have found at corners its best to spend the time to put in a braced wooden post otherwise the strain is too much.  As to getting out, ours haven't, and i know a farmer who doesn't have problems, but i think electric fencing is only really for subdividing, not as a perimeter fence.