The very next day I was speaking in front of about 300 people and then taking questions from the press. I thought I was in serious trouble.
It turned out the press was much easier than the taxi driver, but I was a little nervous going into that.
I don't remember ever having particular difficulties with Dominican Spanish, but I also don't have a huge amount of experience. Just a few random conversations and nothing where I was the only foreigner among a group who already know each other, which is probably the most challenging situation.