The dials used to select numbers (such as times for the alarm clock or dates for the calendar) seem to be unresponsive to my touch - if I move through one by one it is fine, but if I set the dials spinning and try to stop them by putting my finger, it continues to spin for a second or so, meaning I always miss the number I'm aiming for. I don't know if it's related but I find a couple of the MIUI components like that a little slow - the settings app for example. The settings app isn't extremely slow to use but when I'm scrolling I notice a little jumpiness. Maybe I'm just overly picky. Other than that this ROM is very smooth to use and I really love it!