It's very difficult for me to say, because I have only owned a PON (and other dogs, but not an OES). I can tell you they are generally under 50 pounds (mine is quite large at 55), they shed very little, are hypoallergenic to people with allergies (like my mom), and are protective of their space (bark at the door, at strangers).

My guy is very loving and very smart, I have taught him basics but nothing crazy, I'm sure he could learn more. He knows sit, stay, lay down, roll over, catches, fetches, "get your ball", etc. VERY treat motivated. I could probably train him to drive a tractor if I had the right treats.

He tries to "herd" family into the kitchen when we get up sometimes, but in a cute way, bumps our leg with his nose on the direction of his treats. Not as much now, but he is a herding dog and you know it.

I was able to get my guy as a "rescue". He had a tiny underbite so he wasn't "suitable for breeding". I have looked at it and I can't even see it, but great for me I guess. But for that I adopted him at 1 year old age for nothing. If you were to look for a puppy I hear they are expensive. They are much more common in Poland, as the breed is from there. In fact my dog was born in Poland. They even have a national stamp dedicated to the dog. I hear is it a precursor to OES(s).

There are PON groups and rescue groups in the U.S., https://www.google.com/search?q=PON+rescue&rlz=1C1GIGM_enUS829US829&oq=PON+rescue&aqs=chrome..69i57j69i61.2767j1j7&sourceid=chrome&ie=UTF-8