Our building has plenty of dogs. I'd estimate around 40 or so, which it seems condensed at times as it's a high rise building. So Kananga ends up making lots of friends. I think on my floor alone there are probably 4 or 5 dogs.
He has done very well with other dogs. He has a few that he's particularly fond of, while others he just doesn't show as much interest. I know of a couple that have gotten growly with him, although fortunately he never seems to react to it. I think he knows to just keep distance and not cause problems.
The important thing is being cautious around new dogs that the Basenji meets. Keep a firm tension on the leash in case the other dog decides to start growling. After that you can gauge the friendliness between other dogs and know which ones to be careful around.
My brindle boy has always been very kind with other dogs. Usually they approach each other and sniff things out. Every now and then he'll wrestle with a dog he knows, but that's not a common thing for him to do. I've never had him get aggressive with any dogs.