Need New MM Cartridge Recommendation

The compliance rating of the cartridge and its compatibility with your tone arm to avoid unwanted resonant frequencies must be taken into account too.

I assume your Radius has the Roksan Nima tonearm. If so, its effective mass is 10 grams making it a good match with any of the three MM cartridges you mentioned in your original post. If you have another tonearm, then this could be a different story and resonant frequency of the cartridge/tonearm should be re-evaluated to insure a proper match.

Of course just because the compliance match is right, they will still sound different and I would encourage an audition of each if possible. Cartridges, like speakers, are transducers and each brand will sound quite different from one another.

I will throw another in the mix for your to consider also - the Nagaoka MP-500. Sorry to further complicate matters but this cartridge is another world class MM cartridge and deserves to be in your group. Good luck!

The Nagaoka MP-500 could be found for $699 new.  About the same as the OP's other choices.

http://www.lpgear.com/product/NAGAOKAMP500.html

MM cartridges for box speakers, 
MC for panels.

This post must have been aimed at humor rather than fact.  Make an emphatic statement but provide no explanation as to why it is so.  Posts like these are usually jokes or classic cases of hit and run.  In this case, I thought it was a joke.