Well...I guess it depends on the type of fishing you do. I'll explain from my perspective as primarily a bass fisherman and fish primarily electric only reservoirs. What I want is to be able to stand up and cast my lures overhand or underhand at any angle. That said, having the deck as close to the gunwale of the boat as possible allows me to do this. On a 1648 flat bottom, I could do this and have the boat be (what I would consider) stable. Decking most v-hull boats this way would be much more unstable. The mod V would be somewhere in between, but would be significantly more stable than the v-hull. If you decked the v-hull at the floor, it will certainly be much more stable than if your raise the decks, but you won't get the same mobility that you would from a flat bottom.
As a bass fisherman (who wants to stand and fish), I think a v hull is not the best choice. If I did a lot of trolling, I think the v-hull would be my choice.
Hope that helps.