I was REALLY afraid you'd say exactly that. I bought the AHB2 for being a resolution/detail monster, but the flip side is that I knew dynamics would hurt and I'm not sure I'm still willing to give that up. One reason i bought it was to potentially use it for headphones as well. Not even sure how much of a good idea that even is.Yea, those are ribbon tweeters. Maggies draw a lot of current IIRC. The AHB2 may not work as I found them sound very linear, excellent resolution but doesn't have as much "oomph" especially when volume turned up, or for large dynamic as in orchestra recordings. I didn't try running AHB2 as monoblock coz when I bought mine it was during the time it takes 4-6 weeks to get a new one. When I switched to the Spectral which was 300W/ch at 8ohm it's quite noticeable the dynamic is back; however, it lost a smidge of resolution and the bass does not sound as clean (a bit boomy).
So, my guess is you might find the AHB2 a bit light. The LA90 is very similar to the AHB2 but it felt like it has bit more dynamic "power", especially when running as monoblocks.
As always, those are just my subjective impression. I go back to the HPA4 + AHB2 as my benchmark (no pun intended) when comparing with my "new" gears. I never had any Maggies so I cannot really speak for sure, but my friend is a fan and he was running older Krell amps (not the new Krell) which are known arc-welders.
Those LA90 had me REALLY curious as well! I suspected they might be on similar playing fields as the AHB2. However, now Im somewhat tempted to leave the AHB2 in its box, sell it as new, and just wait for some Tyrs. Last week I was comparing Tyrs to some Burson Timekeeper 3x GT. Those burson monoblocks seem really nice, but with less power than the Tyrs. I think people might prefer one over the other based on lifestyle choices.