HooknLine,
I've used the inexpensive Rapala fillet knives for years, and have to agree that once you get the hang of it, you can make quick work of filleting fish. They also sharpen in an instant with the inexpensive sharpners you you can pickup at Walmart or Kmart.
I have nothing against the electric high end models, but I'd think I'd cry if I were to drop one overboard as I've done on more than one occassion during the last twenty years.
If I were to clean a ton of fish at home or routinely at a cleaning station, then I'd go with electric. But if most of your cleaning is in the field then I'd recommend the old fashion style and go manual.