What’s are the negatives of your dog/japanese spitzes in general?

I’ve been reading about this breed and they just sound perfect, almost too good to be true. Friendly, fairly low exercise requirements, low maintenance coat, intelligent, and HEALTHY!!! There have to be downsides though, as there are issues with every breed; what issues have you found with your dogs (e.g. separation anxiety, aggression, barking, difficulty training, etc)?

I just want to ensure that I know what I’m getting into before I adopt one of these beauties.