Manufacturer user interfaces (UIs) can be a bit of a hot-button topic in the Android world. Some prefer vanilla Android, à la CyanogenMod. Others have no issue with them whatsoever, and even actively seek to restore some of the functionality. (Others still prefer to roll their own, or like the ability to switch at will... but I digress.) Further, your feelings on manufacturer UIs may depend on which manufacturer and which UI we're talking about.
With all that in mind, how do you feel about manufacturer UIs? I don't really need to tell you to sound off below, and drop a line in the comments to elaborate, do I? Didn't think so.