Like Tommy, I have exclusively used power wigglers for about 15 years and I consistently out-fish those with natural baits. Also (as Tommy said), movement is key, but not all movement is equal - I employ a wrist roll technique which causes more of a stationary flutter than the standard up/down jigging motion; simply raise/lower your bait while doing this to fish the water column. (Having a camera really helps to see what you are doing and how the fish react... this will dial you in more than anything.)
One thing I do differently (that may make the difference for my higher catch ratios) is a take a pair of fly tying scissors and cut the wiggler - in line with the bait - half way up the body from the rear of the bait twice at 90 degrees... this gives you four tails, which I cut each in half to make eight. This ends up with a micro tube which I think looks like a freshwater shrimp. I also think the "skirt" has more water friction and allows the fish to suck the bait (hook) in much easier.
The nice part of plastics over natural baits is they don't ever die, need to be fed or kept cool... plus, fish can't squirt the guts out of it and leave you with just a skin.
