Which amp is best to drive Magneplanar 1.6's?

Audio Research 100.2 200 watts into 4 ohms. Great combo

Another suggestion- CJ Sonographe 400, which is all solid state. ALmost too much bass for the bass-challenged Maggie MG12's (which valiantly tried and failed to produce anything more than distortion below 40-45 hz with the CJ), but the 1.6's will handle it just fine. Around $600 used.

I would definitely give the Odyssey stratos stereo or monos a listen. They are high current for those power hungry Maggies and they are very musical. The tonal balance should be just right with the quasi ribbon of the 1.6.

Bryston 7B-ST at about $2600 used. Friend of mine uses it with his MG 1.6 with great success. Clean, rhythmic and articulated bass with tautness.

I'm using a Mark Levinson 335 with a Rel Strata III sub.
The 335 drives the 1.6's nicely.