Never flown a bonanza, but a Baron isn't what anyone would confuse with "quiet", and the 99 is like trying to fly with a guy using a jackhammer in the other seat. It's absurd. I think I flew a Sundowner once way way back in the day, and was equally unimpressed.
I'm just confused by the "rep" that Beech has for being extremely well built. The 99 and the MU-2 are sort-of-kind-of-similar-type airplanes. The MU-2 is of higher quality in every conceivable category, both subjective and objective. Yet Mitsubishi isn't known far and wide as a paragon of quality...Methinks it's a self-perpetuating myth.