Obviously 2 engines are better than one in terms of redundancy, but looking just at engine reliability a single turbine gives you MUCH lower chance of failure than a single engine failure in your Baron.

There is a lot to like about a single-engine turbine (jet or prop). Greatly improved reliability over piston twins, good power and speed, but reasonable (almost piston-like) fuel burns. A twin jet is going to be expensive to run, even a Mustang.

The Meridian, TBM, PC-12, Caravan crowd have been enjoying good reliability and economy for a long time. The Vision and PiperJet I think have a chance to be good contenders.