Pro's: cute as h*ll, Highly trainable, Highly intelligent., smaller = cheaper to feed, vet care,etc. Great to cuddle with their soft fur. protective of their home/yard..not mean just will let you know if something or someone is creeping around.....has been known to chase off critters....
Con's: can get bored easily and get into trouble fast, likes to herd everything! kids,cars,etc . so it must be taught what is O.K. to herd and what is not!, can become a killer if not handled right" a killer of ducks,geese,chickens,other small critters" They think they are 10 foot tall and bullet proof...pro and con in my book.....They shed a lot as they are a breed with a thick under coat, brushing or trimming them helps with this.
Personally I love the breed...they are very nice sized dogs, not to big but not a small fu-fu dog and can go all day, they are a working breed so they do, do best when given a job of some sort.."does not have to be herding work" they excel at a number of things." They are so smart training them is always fun..you have to be smarter than the dog to get them to do what you want. They do not react well to harsh treatment, they tend to shut down and go into whatever mode. They can get out of control very easy with lack of training much like border collies. They have a lot of energy so unless you'll be using the dog as a working dog you'll need to find a way to "burn" some of it off....many love to play ball,Frisbee,go for a run,etc....they don't look like they are "fast" moving dogs but trust me they are lil 4 legged jet packs.
How old is the dog? Does it have any issues? chases cars,herd kids,etc?
One nice thing I have found about them is unless a bad behavior is really ingrained into them most can be retaught right from wrong......also most older dogs that maybe lacking in the obedience dept. can be taught with no more work than a puppy to mind very well.....we see a lot of them in the rescue I work for....many people just think oh a cute med/small dog to have around and go buy one...only to get it home and find out they have a 25-30 lb ball of energy that starts to find interesting ways of letting it out when the owners don't have the time to put into the dog. Good Luck! and BE CAREFUL!!!!!!!!! they are 100% lovable and addicting.
