i have felt that while sanders and bryston amps surely have the ’balls’ to drive maggies well, to my ears they lack the last desired dose of refinement, tactility and fullness/bloom that i feel is very beneifical for maggies (in this category i include amps from spectral, levinson/proceed, non class a krells and so on) -- we all hear differently, have different tastes, but this has been my own experience
that said, current gen maggies big and small are thankfully voiced sonewhat warmer/fuller than earlier ones from years ago, but are they remain quite demanding in terms of needing to be fed very pure treble and mids
i still prefer solid state amps from pass labs (ideally high class-a biased ones), hegel, ayre, accuphase and that ilk, that bring an exceptionally high level of treble purity and refinement to the sound (alternatively, tube/ss hybrids can often do very very well with maggies)