The 2xII is somewhat better than it's replacement, but quality wise, it doesn't equal the old 1.4x convertor or the 1.4xII convertor.
I have used it for sales of sports and equine shows, but if I can use my old or new 1.4x convertors, I much prefer to do that because I know I'll have better, saleable images a much higher percentage of the time.
There's a reason the 1.4x convertor costs more than the 2x. It's a better product. If you are going to purchase only one convertor, you'll be happier with the 1.4xII.
The 2x is great to have in camera bag. It works well with 70-200L 2.8 lens. Just don't expect as sharp an image as 1.4x.