First let me say that I am a dealer for LAMM and I will try to be as unbiased as I can.
I have had both the M1.1's and the NL12 and liked both. Overall, I prefer the Lamm M1.1 amps, but there were a few things that I preferred about the Edge NL12.
The LAMM's had a naturalness and ease of presentation that the Edge could not match. I would say the LAMM's were also quite a bit more musical. With a speaker that needs A LOT of power, the Edge may have a slight edge :)
With quite a bit more power the Edge has a real grip on things that, while not a weakness in any way for the LAMM's, is one of the real strengths of the NL12.
Overall, if the two amps I mentioned have enough power for your speakers (They would have to be ridiculously hard to drive if either of these amps would not work), I would recommend the LAMM's just for the musicality.
Good Luck!