Wowza, the grohman is nice. But $$
Are the dexters a flexiable filet knife? Or a boning blade? Or is that really the same.
Depends on the style you choose - they have full on fillet knives and they also have boning/fillet style blades. I have several of this one and it seems to work well for my use.
http://www.dexterrussellcutlery.com/dexter-8-narrow-fillet-knife-31609-p94813/I also have a couple of what they call the Wide blade fillet I use on bigger fish.