I had the good fortune to spend 4 years on a Raisebeck B200 Super Kingair, 1982 model. I've got to say they're pretty bulletproof, and we worked it hard into gravel runways for most of it's life in ISA + 30 conditions- it never missed a beat. The hi flotation gear was a pearl!
Perhaps the only thing that'll kill you on earlier models is the pressurization system, it has been known to subtly fail causing more than one complete crew/pax incapacitation and crash that i know of, and some of the PT6 -42's were a little susceptible to icing even well below -40C, when super cooled droplets could attach to the inlet screens, then subsequently break off and be injested, causing compressor damage. (Not a problem if you ALWAYS put the ice vanes out in cloud)Apart from that, not much else will go wrong.
Enjoy.