Piston V.S Turbo Prop

Any one have any sales advice on piston twins v.s turbo prop twins. I'm
currently in the process of aquiring a charter buisness that operates 2
navajo aircraft. I've heard some people say that the days of the piston twin
in commercial charter work may be coming to an end. Now I don't know if it's
just because of the problem with some of the cessna piston twins or just
that large corps want to and spend the extra $ on the reliablity and comfort
of turbines. I can basically offer services out of my local airport at less
than half the cost of the guys with the turbines. Does anyone feel that the
issue with the cessna twins could actually increase the value of piper
twins, or is the problem spread across both companies.