Have to chime in. All the pros use long shanks, However they buy the quality burs. They have carbide heads and hardend steel shanks that take ALOT of imbalance to break.
Good supplier? SGS Tool Company - A Leading Manufacturer of Precision, Solid Carbide Cutting Tools.

That said its important to have a good quality grinder and collet to ensure very little runout at the end of the cutter.
As far as long shanks being hard on the bearings, maybe on the cheap grinders, but on High quality grinders ( ie milwaukee,Makita or Ingersoll) , electric or air, you wont have an issue.
My 2­­­­c

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Life long project. No it wont ever end....