Asynchronous Double Speed Mode for UART

[airman00]

Hello All,
I was playing with my ATmega325P and using internal 8MHz clock, and needed 115200 baud communication. To my dismay this was impossible because 115200 baud on normal UART yields 8.5% error.
A friend recommended to use Asynchronous Double Speed Mode, which always yields a lower error of -3.5%. All I had to do was set the register (U2Xn = 1)

Are there any disadvantages to using this mode?