It reduces reducing  heat rate, and hence reducing operating cost

It increases the complication of the palnt

It reduces irreversibility, thus the heating process in boiler tends to become reversible

It require less steam flow rate for given output power

larger capacity boiler is required for given output

smaller capacity condeser is required for given output

turbine output decreases due to extraction of steam

all of these

It reduces turbine blade erosion  due to moisture

It requires less maintenance

It increases turbine output for given steam flow rate

It increases temperature range in the boiler, thus more thermal stresses are set-up in the boiler

It require less floor space

It increases the workdone through the turbine

It rdeuces erosion of turbine blade

It increses thermal effiiency of the plant

fuel consumption is increased by 4-5%

it is prefered for low capacity plants

the complexity of operation and control increases

all of these