Boy, I've never heard about so many knife gadgets!!!! It seems to me that if you consistently sharpen your knives they are easy to keep sharp. I use one of the Rapala filet knives and sharpen it before, during and after cleaning (depends on how many fish) and only use one of those cheap Rapala knive sharpeners. They are plastic with ceramic rods molded into them, you just draw the knife through it a few times and Viollaa, it's sharp. It came with the knife, I think they cost about $10 separately. Been using them for years.