No, they do not.

Yes they are

You do not want to clean the filter you can clean the bottle with a mild detergent.

Yes the filters will fit the older bottles as they style of the bottle hasn't changed

Yes as long as it is a 28oz flip top or 24oz pull top bottle

Yes this filter will work. This is just the replacement so if you do not have a bottle you will need to purchase it. here is the link to the bottles Seychelle Advanced Water Filter Bottle

It has a filtering capacity of 100 gallons.

I would guess the bottle would hold 25 to 26 ounces of water with the filter in it.