At a very small weight penalty id take the TT,if you've had or have one. A 6.5 doesn't need that high of mag for what it is. I would myself like to look threw a newer March to compare to mine.Mine is optically with my mark 4. I evening at 1/4 off my hot tub.I can see the barbs on fence with my mark 5 and not my march.The mark 5 is much clearer.My March is basically a 20 x , past that it looses definition.