Brimac, nice to hear that the MJs are working out for you. A pair of Ref200s is the way to go.
Back to your question to using alternate cables than the ones that came with the subs. For one thing I did not care for the Speakon cable that came with the subs. The bass was there but did not have any life too it. Fortunatley I had an extra set of Cardas Crosslink speaker cables not in use with bananas on the amp end. As you can figure out, I cut the speaker ends off the Cardas's and put the Speakon connector on them. Let me tell you, ever see the Maxell ad with the guy sitting in the chair with his hair being blown away. Thats the result I got. Clean, tight, forcefull, tunable bass. With stereo subs thats what makes really worth it. As per the power cord, again I had a spare pair of Van den Huls that I put in with the subs the day I got them.
For even better bass$, now I am using the Synergistic PhaseII Speakon for the high level input and a set of Synergy for the low level. Have the low level set around 20, high level at 45, tweak the volumes, program the remotes and you are good to go. I ended up putting the remote eyes under the main amp so I can use one remote to control both subs at the same time. If you need an extender, go to Radio Shack.
Glad they are working out for you and as they break in, it will get better.