I've used Kencove, Gallagher, Stafix (and Tru-test), and Cyclops. The Gallagher's, with proper lightning arrestors installed, are still going, albeit the most expensive. I would have thought the Stafix and Tru-test would have been on the same level as Gallagher, but have had a few more issues, some their faults, some mine. (no lightning arrestor). The Cyclops was a good bit cheaper than the others mentioned, and do not require a lightning arrestor. However, they have fuses that are used instead, that must be checked and replaced. I've found that a heavy load on the fence if not found in time will blow the fuses. For the money, I still like the Cyclops, and have successfully had one repaired in Alabama quite affordably. I have not used Parmak, so I can't compare.