I got a test pack for X-mas this year and settled on the Black
I went with the Black for a softer feel around the green and off of the putter. The X is maybe a yard longer than the Black. The feel off of the putter was the difference. I was a Bridgestone player, but the feel off of the putter was a little harsh.
I find this ball to be great in the wind. I was playing an OnCor Elixr that the wind was eating up, so I switched to a Snell and it was night and day.
I just received 2 dozen Black in yellow
The yellow is the easiest to see yellow I have ever played with.
This ball is the best deal in golf.