There are two sizes of Mini-Mag's. The larger one is called the 8/10 and it is rated for 300 to 400 grain lines, which puts you in the 10 wt range.
I like these rods with a shorter head length shooting-head style line. The Sage Bass line is (or was) a 330 grain shooting head line and it worked very well with the Mini-Mag. There are other shooting head style line available including Rio's Outbound Short, Orvis Bank Shooter, etc.
Several people have also been happy with standard 10 wt lines. My vote would be to look for a shorter head length with more of a bass taper style line. These rods are usually fished at shorter distances with really heavy flies.
I have a 10 wt SA Titan tape line (designed for casting large flies) and I noticed last night that Sierra Trading Post just put some of these lines on sale. If you want to try casting it with your rod, bring the rod out to "Texoma on the Fly" tomorrow at Lake Texoma and I'll bring that reel with me.
FFF Certified Casting Instructor
TFO Pro Staff