I've kept Polish.....it may help us to help you if you can post some specific questions, concerns or considerations you have that you want to base your decision whether they are right for you or not on.
From the posts I've read here, Polish hens are more likely to be picked off by a predator, they are sometimes bullied in a mixed LF flock. They are more prone to head injuries and neurological problems due to vaulted skull. And their productivity is not as good as it is with other heritage breeds. Do your homework carefully before buying them.