Go with the Mirage M3Si, These speakers Disappear and all you get is a huge wall of sound with great depth and definition. I use to own the 1st series M3's and I loved them even more after I sold them (wife). I kept them for 10 years. Never have I heard music presented so well and with such SLAM, delicacy, detailed, beautiful sound. Mirage designs these speakers to have the grills left on, So if you like to take them off THAT could be a deciding factor. You cannot easily remove them either. So make sure the pair you buy has excellent looking front and rear grills. Never heard the NHT Sorry. Regards,
Matt
Matt