the term "precision" in relation to comparator is uncertain,- better to define sensitivity level for given delay/speed, and maximum offset value. For some type of ADC (e.g. SAR) offset doesn't limit ADC's resolution. The term "bandwidth" for comparator also don't clear define it's speed,- contrary to OAs it can incorporate many stages (>>2) and don't require to be stable in close loop configuration. Sensitivity better 1mV with delay <1ns is realistic target for 0.18um node, but offset <1mV isn't without experience, I think.