I have used Good karma when we adopted a dog last year and they were great. They were extremely thorough and very careful about matching the right owners to their dogs. We have two young children and an older rescue dog (from the UK- pre kids) and they took all of this into account.
In response to previous posters, no, adopting a Romanian dog won't make a difference to the huge stray problem they have in that country or others similar, but it is preferable, in my view, to give a home to a stray if possible. We couldn't adopt a rescue in the UK due to having young kids. They also do a lot of work to contribute to neutering programmes which are key to managing the issue.
Our dog is lovely. She's really affectionate and has responded well to training. No problems there, and our UK rescue (who is anxious) has far more problems. However, as I say, Good Karma took our circumstances into account when matching us, and so we got a young dog who was confident - she had been living on a farm with her siblings and mother, and was well looked after by a local vet who the charity works with. We wouldn't have been matched with a 'feral' dog, but I know lots of others who have had street strays from Good Karma through the fb group you can join after adopting, and there's so much support, all seem very well adjusted dogs.
I don't think all organisations are quite as strict/picky and I've heard quite a few stories of bad experiences with people adopting from abroad, so it pays to do your research into the different charities. Ones that rehome loads of dogs might not be as thorough.
Hope that helps.