You should stay with the franchise as long as you enjoy it I suppose. But its stupid to say you know you'll enjoy it forever. You can't say. Stick with it as long as you enjoy it. Their biggest hurtle is the screenplays, which have become pointlessly redundant, part 4 being basically an homage of part 1 and part 5 being largely a flashback that negates part 1. I won't say I hate the franchise at this point but they've placed all of the emphasis when talking about the 'making of' on the gore, which relegates the film to what naysayers have been calling it all along, torture porn. When they start promising a good story or even a thrilling movie I might rush to the box office, but only bragging about how much more blood you've shoehorned into the franchise does nothing for me.