Similar? I don't think so.
'New' Baron or 'old' Baron ie pre- or post-cockpit reshuffle is also a significant factor.
Old: Gear & Flap selectors are switched. As are throttles & RPM levers.
All: Emergency gear extension very different. Handling different - more inertia, greater speeds at which things happen. Performance much better for the Baron (except asymmetric at full load. Light twins are all pretty much as bad as each other...). Continental injected engines so good luck for hot starts until you get the hang of them. Significant fuel pump differences too. Who would have thought the fuel pump could cause rough running or even stop the engine? Fuel flow leaning in the climb to be considered.
You definitely require an endorsement i.a.w. the rules. A Baron is *not* classed as the same type as a Duchess. Unless the rules have changed, removing endorsements for multis <5700 kg?
If you're experienced on Bonanzas then a Baron isn't hugely different to the Bonanza. That's a much closer comparison than a Duchess.