Sunfish boom blocks (both swivel or only one swivel block)

On the stock Sunfish the front boom block is not swiveling and the rear boom block is a swiveling block. I am installing a ratcheting mainsheet block and I wonder if I should change the front boom block to a swiveling type to avoid binding. I read in another thread that the front block can be changed to a swiveling type per the class rules. Is there any downside to changing the front boom block to a swiveling type?