I have played with all of the Predator shafts and the OB+ Pro and OB+ Classic. I can only imagine that the OB+ XL is just as good as the other two if you're looking for a large shaft.
The Predator shafts definitely have lower deflection but they hit completely dead compared to the OB's. The OB shaft cost is lower and after you adjust to them, there it no comparison as to which one hit's better or spins the ball better. They feel like solid maple shafts with low deflection properties.
I've had friends who have been using Predator shafts play with my OB 121 and they will miss ball after ball not knowing how to adjust. I explain that because the ball is coming off the tip with so much power transfer, they can let the cue do more of the work. Once you figure out the amount of power you want to use for a shot, pull back about 20% and magically they start pocketing everything from everywhere.
I absolutely hated the old design but OB really has something special with the new solid SR-6 lamination.