Sorry, I didn't realize that you were talking about banking the 8. Is the Z- bank the same as banking the 8 ball three in the side? If so it doesn't look like the angle for that shot is on. If it is I would shoot that shot.
Dr. Bill
The three in the side does not at all look like it is on. If it were, I would change my mind and shoot at it, foregoing my concern over the dangerous position of the 4 ball and maybe even leaving him something on the 7 ball. My reason being, is that the three in the side ( for me) is at the minimum, an even money shot to make. Three in the sides are much easier than people think. Remember, I said I was probably only 33% to make the Z bank with the 4 ball. Insuring the speed on the 4 ball that would guarantee the pocket to be blocked would probably reduce my percentage to 25%.
To try and win the game, and also to be certain I couldnt lose it, I would have to fire at any even money shot.
Beard
For anybody that wants to give me two shots at the 3 in the side at Tunica, the window will be open.
But alas, I have digressed. The opinions in this thread are based on the 8 ball 3 in the side option not being available. I fudged the diagram slightly to show how percentages can completely affect your shot choice.
To elaborate further, if the two balls hanging in the pocket were not hanging in the pocket but were bankable, the even money 3 in the side wouldnt look so good anymore. Especially if I was going to leave a decent shot. I would be looking much harder at the Z bank 4 ball, and there is also a good chance I would just play some sort or safety, something maybe like Billy suggested trying to take some balls out of play.
Beard