How fast do you want to do?
If you do any snooping on 6mmBR or other forums, you will quickly find these cartridges being discussed from a competition perspective.
All have their place. Just depends on what you are trying to do.
AS for performance, at the same operating pressures and effective barrel lengths, the 6.5X47L/Creedmore are slower then the 260R which is slower then the 6.5 Mystic/260AI/6.5 Swede which are slower then the 6.5 Swede AI/ X57 which are slower then the 6.5-284/'06's.
There is simply no replacement for displacement. All of these can be made to shoot equally well !!!
Remember that if you can't duplicate some fancy powder technology or must use a vault strong action, that is not desireable performance to me.
The 6.5 X47L is gaining in popularity due in large part to the super strong Lapua brass. Unfortunately, you better have a nice tight strong action and smooth barrel or you will not be able to get the velocities levels some quote. This is not an ideal hunting set up in my opinion.
I prefer to run a larger case at lower pressures in a hunting rig. Far more reliable when things get wet and/or dirty.
For a range rocket with rules, mag restrictions, time constraints, whatever, sure. Each has been designed to meet a performance goal.
Jerry