Pros:
Less rotating mass, Less chance of the balance shaft belt failing and taking out the timing belt.
Cons:
More vibration from the motor, Pretty much have to pull the motor to remove them.
Thats about all I can think of so far. The vibration really isnt that bad, if you have solid motor mounts its worse but only around a certain frame of RPMs.
Just dont forget to put the nub in that replaces the rear balance shaft and gets bolted to the oil pump gear or chances are your motor will be toast within 100 miles!
Threaded Mode