There is a legitimate amount of time that an employer would be able to justify for dual received in my opinion and that of other similar posts I've seen on this subject before. I mean the initial type rating is about 28 hours or so of left seat/right seat time. If you were to have 100+ hrs of dual received in a King Air 300 (and do you mean BE-300 or an actual King Air 300?), I would think it would raise an eyebrow.