I have the Pork Barrel brake line lock kit too. The electrical draw by the locks is about 1 amp, so you can leave it on for at least a couple days. However, you won't want to leave it unattended with the locks engaged without leaving the transmission in gear, for safety's sake.
This kit should not be considered a replacement
for a mechanical parking brake. It is designed to supplement the stock (or Spidertrax) parking brake, and is really intended for off-road use. For instance, if your Weber stalls out on a steep waterfall and you don't want to try backing down, you can just flip the switch, let your foot off the brake pedal, and use the clutch and gas to get the engine going again. Then keep your revs up, start letting the clutch out until you feel it pulling hard against the brakes, and flip the switch again to drive right on up. Or, on flat rockcrawling where you'd normally be throwing your right foot from gas to brake to gas to brake to control forward progress, you can simply step on the brakes halfway, flip the switch, and then drive through the brakes. This makes forward progress much smoother and more controlled.
Scott and I love our line lock kits. Highly recommended!
-- Geoff Beasley
Suzuki Tech Editor: http://www.Off-Road.com