I have found the Yoast SEO for Word Press to be my first choice when it comes to top placement in SERPS. I have tried others and was not having as much success.
I have had some support issues and the staff have always been prompt. They even have gone beyond the call of duty and helped with code issues on my site that they did not need to because it was not related to their product.
Great job to everyone at Yoast.