Magnum Dynalab 308 drive Magnepan 1.7 or 3.6?

Generally Maggies are an easy load. Moderate phase angles and no huge dips.
see link to measurements.

http://www.stereophile.com/content/magnepan-magneplanar-mg36r-loudspeaker-measurements

Now, the real questions to me are 1. how loud do you play your system?
2. how large a space? 3 Do you have the space to devote to panels? You will need a minimum of 3 feet behind the speaker to the 'front' wall.
Also, do you have a sub? If yes, will you run the panels full-range or allow the sub to handle below crossover?

Another couple considerations for Ctunney::
Except for the 20.1 which is push / pull, Maggies are not the same front and back.
I personally prefer 'backwards' and listen to the pole piece side NOT the mylar side. Magnepan made the switch some years ago, probably because people liked the hotter (IMO) presentation. My 1.6s came with a resistor to lower the HF level, if I preferred.
Also, you can place them tweeters 'in' or 'out'.
So, If you get panels, you'll have some experimentation to do.
I'm not a fan of the sideways setup. Others apparently are. My speakers are about 65" apart, inside edge to inside edge and are toed in about 11 degrees.
Once I did the detail setup, I measured so I could put them back exactly.

Try to make compromises so you CAN get at least 3' behind the speaker. This is one of the things that everyone agrees on. Toe in is the other. NEVER straight to a wall.