I have been using a Flylogic FL12 for most of the Rio lines and the New SA xlt lines.
The largest lines will have to use on of the micro type backing.
There is one problem and that is with the Grandspey 10/11. It is so large that you only have about 100 yards of backing on the reel.
The Windcutter, Mid-speys, and Tri-tip will fit with plenty of room.
The drag system wills uses a torque converter for zero inertia startup
I hope this helps
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