I just did some research and the only cam up with a few cons;
-They shed a lot for being somewhat small
-Prone to obesity (shouldn't be an issue if you give them needed exercise)
-They are very protective of their owners (which isn't a bad thing but may lead to barking at neighbors outside if they aren't trained not to)
-Very energetic which may lead to difficulties training as a puppy but gets better the older they get
-Very intelligent which is a good thing but may lead to difficulties if you're not strong willed
I've been looking into them more and more lately and really like them. It seems that if you can get through the puppy stages with these guys, that they make amazing dogs. Great dogs as far as being able to live indoors but enjoy and have enough energy for outdoor activities.
Overall, it seems that they have a bunch of positive traits and if you know what you're doing, you'll be fine.