As with many other bee questions, generalities don't give us much insight. 
We need to consider the many factors which make the difference between a 
stressful move and a move which is virtually stress-free.

Increased queen loss is one well-known downside to moving bees. Bee and 
brood loss are others.   Drifting on arrival can be serious.  These can be 
minimized, though with understanding and controlling the factors involved in 
a move.

The amount of stress experienced by hives being moved is largely dependant 
on the  expertise (and luck) of the beekeeper and trucker, the timing, and 
the choice of locations.

The design of the hives and recent history are factors, too.  Loose, 
swinging , shifting frames can do damage.  Excess or insufficient airflow 
can affect colony condition.  Delays in hot sunny weather and water 
shortages often damage loads.  Hives with lots of brood are vulnerable 
compared to hives with little brood.

With luck, good procedures and good timing, the stresses of the move can be 
insignificant compared to the advantages for the bees.

With bad luck, bad handling and poor choice of locations, the result can be 
poor colony condition or death. 

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