I would not intentionally feed my cats any kind of live prey. I think it's cruel. My cats have plenty of nourishing food and plenty of toys, so I don't need to resort to that to feed or entertain them.
If a mouse gets into my house and they kill it before I get a chance to take it outside, well, that's just nature taking its course, but I'm not going to deliberately let them play violently with another animal. What they would do outdoors isn't a factor, since they are completely indoor cats.
I wouldn't personally feed them a frozen mouse either because I have a pet mouse and it would feel weird, but I do think that's more humane and hygienic if you feel your cat absolutely must have mice.
If a mouse gets into my house and they kill it before I get a chance to take it outside, well, that's just nature taking its course, but I'm not going to deliberately let them play violently with another animal. What they would do outdoors isn't a factor, since they are completely indoor cats.
I wouldn't personally feed them a frozen mouse either because I have a pet mouse and it would feel weird, but I do think that's more humane and hygienic if you feel your cat absolutely must have mice.