Besides just naming a kit, I will talk about manufacturer. It really does matter. Aerotech are mid power kits but are in my opinion easier then a surface mounted fin estes rocket. For a true MPR you need fins that are attached without a snap on unit. LOC kits are nice and simple, but the elastic is not good for larger rockets. PML has some nice kits and the best materials in my opinion, their QT tubing is not good for very large rockets or mach busters but is great for a mid power rocketeer, just sand it. The G10 fins and rings are also very nice. The cones are sturdy and the pistons are nice but I dont personally like to use them. I would stay away from surface mounted fins and MPR rockets with fins that go through a slot but not the the motor mount tube. For a very strong bond the fin should go to the motor mount tube and possibly be sandwiched between two rings.