A bit slow to train while very young, getting easier and smarter as they age. Seem to be very sturdy as they tackle each other quite often. He is around 85 lbs and she is 70 and it is currently August. With his weight he definitely has the edge when playing but the female never gives in and she can take him down with some pretty smart maneuvers. They play in the same fashion as we play football and run down our 100' by 200' back yard in a hurry. She will lead him around by grabbing his collar which is quite funny. All in fun, but we have to be careful when the grass is wet or has dew on it. When it is wet, it is not safe for them to play like they like to. We have to monitor them constantly when playing in the yard as they can get too rough! They are now about 95% good at staying in their own yard and may occasionally chase one our cats into the neighbors yard, but they now know where the boundaries are and that they are not allowed out of their yard without having a leash on. We have no fence and we do have electric beep/shock collars on them when they go outside, but I think in another week we won't be needing them. They have extraordinary hearing but they can play the game "I don't hear you." Their very loud & persistent barking at anything that moves can be daunting when they are young, again they are getting better as they get older. They like to play with our 14 year old German Shephard/Chow (Max) and they actually seem to look after him. He is getting older and fragile but his bark or nip still rules! Max was getting very lazy last year and that is why we went to look for a companion for him and these two pups brought life back into him that we thought was gone for good. For some reason when Max is up moving around the house, the pups always want to walk in front of him and put their face right in his. Not sure why, but they seem to like that he is up and walking around and they do coax him to play and sometimes he does. The only notable problems we have had with the pups is throwing their food up (we've learned not to mix soft food with hard food because they swallow the hard food whole when doing this, give them smaller portions, and don't let them gulp so much water, especially have coming in from out side (yes they always have access to water, they just tend to drink ALOT after playing), and just within the last month we have to continuously clean their ears which seem to be draining. We fill up two kiddie pools for them when it is hot and don't know if this is what started the ear issue, as they love to put their head underwater, but we just check them once a day to be sure they're as clean as we can get them. [I would not recommend having these dogs in a warmer climate if you do not have air conditioning] As I was reading other replies, we too love our dogs way more than we should, but how does one control love? Big dogs are a chain and ball for people that like to travel but we chose them over that freedom when we brought them home. We would do it again! We like to allow our dogs to have fun and as much freedom as possible rather than be constant correcting and I believe our dogs reward us for that freedom as they are truly Happy Pups! They still chew the stuffing out of a new toy almost on a daily basis but hey... they're only here once. Please don't clip their hair or remove their dew-claws (we do trim them)! The hair and claws are there for a reason and if God didn't want them to have them, they wouldn't be there. If our dogs haven't torn a dew-claw off, I don't think it's a concern. God Bless!