I've operated B200's, C441's, MU2's and SWIII's, but no 690's, they all have there good and bad points.
For maintenance, the MU2 was the least expensive, Merlin the highest.
For handling, I don't know how you could beat the feel of a King Air 200, also, you can back up a full Chevy Suburban and load it with no problems.
If you were doing some long range stuff, the CE441 does great, but the handling was crap compared to others, great trailing link gear though.
If money wasn't a factor, I'd want a King Air 200, but as an owner operator operation, give me the MU-2 Solitaire, this aircraft was designed right to begin with, high wing loading for handling in turbulence, landing gear the strongest of all mentioned, adapted off the F-104, fabulous flap sytem utilizing 85% of the trailing edge with an operating roll rate of an F-4 when fully configured, never got boring!
The worst handling IMHO was the Conquest, yes it did climb, but I seem to remember a low (in comparison) Vmo and the nose kind of waggled around.
Cheers.