Is the MK6641 a good everyday watch?

Yes, if you want a dressier look daily. The quartz movement keeps it accurate with little upkeep, but the steel bracelet makes it heavier than a simple leather-strap watch.

How does it compare with other Michael Kors women's watches?

They share the same quartz platform and brand styling. Differences come down to case shape, dial design and bracelet finish, so pick the look you prefer rather than expecting better internals.

Does it need a battery change?

Yes. It runs on a quartz battery, which typically lasts a couple of years and is replaced at a jeweler or watch shop.

Is it water resistant?

Michael Kors fashion watches are generally rated for light everyday contact with water, such as hand washing. Avoid swimming and showering unless the caseback states a higher rating.